Family Descriptions
for
What's Blooming at the
Los Angeles County Arboretum




The family descriptions below are brief ones, intended merely to give a few interesting facts about some of the many families that are currently represented by the extensive collection of the Los Angeles County Arboretum. They will include for the most part numbers of genera and species in the families, significant members of the families, derivations of names, relationships to other families, and ranges and distributions in the world. Taxonomy is in a constant state of flux as it has been since the days of Theophrastus, Dioscorides, Pliny the Elder, and the great Linnaeus. The major taxonomic systems are the Dahlgren system of 1975 updated 1989, the Cronquist system of 1968 updated 1981, the Thorne system of 1992 updated 2000, the Kubitzki system of 1990 which in its early volumes resembles Cronquist and in its later volumes resembles APG, the APG system of 1998, and the revised APG II of 2003. The most recent published work I am aware of is Heywood's Flowering Plant Families of the World (2007). No doubt other systems will arise as a result of more refined genetic and molecular analyses. Consequently, many botanists disagree on phylletic relationships, and so the numbers of genera and species as given here for any particular family, and the circumscription of genera and species within particular families, should be considered as only approximate and as a matter of educated opinion. I wish it to be clearly understood that I am not an authority on plant taxonomy, simply a collector of information from other sources, relying mostly on Heywood, and I present it here simply as a supplement to the photo gallery. Please click on the links below to go to the individual family descriptions.


  Acanthaceae
Agavaceae
Aizoaceae
Alliaceae
Alstroemeriaceae
Amaranthaceae
Amaryllidaceae
Anacardiaceae
Apiaceae
Apocynaceae
Aquifoliaceae
Araceae
Araliaceae
Arecaceae
Asphodelaceae
Asteraceae
Balsaminaceae
Begoniaceae
Berberidaceae
Betulaceae
Bignoniaceae
Bombacaceae
Boraginaceae
Brassicaceae
Bromeliaceae
Buddlejaceae
Buxaceae
Cactaceae
Calycanthaceae
Campanulaceae
Cannaceae
Caprifoliaceae
Caryophyllaceae
Casuarinaceae
Celastraceae
Chenopodiaceae
Cistaceae
Clusiaceae
Convolvulaceae
Cornaceae
Crassulaceae
Cucurbitaceae
Cupressaceae
Cycadaceae
Dipsacaceae
Ebenaceae
Ericaceae
Escalloniaceae
Euphorbiaceae
Fabaceae
Fagaceae
Geraniaceae
Globulariaceae
Grossulariaceae
Hamamelidaceae
Heliconiaceae
Hemerocallidaceae
Hyacinthaceae
Hydrangeaceae
Hydrophyllaceae
Iridaceae
Juglandaceae
Lamiaceae
Lauraceae
Leeaceae
Liliaceae
Linaceae
Loganiaceae
Lythraceae
Magnoliaceae
Malpighiaceae
Malvaceae
Melastomataceae
Melianthaceae
Moraceae
Myoporaceae
Myrsinaceae
Myrtaceae
Nepenthaceae
Nyctaginaceae
Oleaceae
Onagraceae
Orchidaceae
Oxalidaceae
Papaveraceae
Passifloraceae
Piperaceae
Pittosporaceae
Platanaceae
Plumbaginaceae
Poaceae
Polemoniaceae
Polygalaceae
Polygonaceae
Portulacaceae
Primulaceae
Proteaceae
Ranunculaceae
Rhamnaceae
Rosaceae
Rubiaceae
Rutaceae
Salicaceae
Sapindaceae
Saxifragaceae
Scrophulariaceae
Solanaceae
Sterculiaceae
Strelitziaceae
Theaceae
Tropaeolaceae
Ulmaceae
Valerianaceae
Verbenaceae
Violaceae
Xanthorrhoeaceae
Zamiaceae
Zingiberaceae




The Heliconiaceae is a monotypic family containing the single genus Heliconia. The name comes from Mt. Helicon in Greece where the mythological Muses supposedly lived, and reflects the affinity of this genus to that of its close relative, Musa, the banana. It was formerly included in the Musaceae family. Other close relatives in the order Zingiberales are Strelitzia (bird-of-paradise), the gingers (Zingiberaceae), and the canna lilies. Heliconias are distinguished by their inverted flowers and fruits which are drupes. There are between 200 and 250 species in the family, most native to the Americas anda few in the South Pacific. What most people take as the flowers are actually showy waxy bracts which enclose the true flowers. Other common names include lobster claw, wild plantain and false bird-of-paradise. Heliconias are important sources of food for certain for-
est hummingbirds and some bats.
 

The Grossulariaceae is a small family
which used to be considered as part of the saxifrage family but now seems to be widely recognized as a separate taxa. The family name comes from a genus now considered as a synonym of Ribes, Grossularia, whose name is taken in turn from the Latin grossulus meaning a small unripe fig. As far as I can determine, the Grossulariaceae is now thought to be a monotypic family containing the genus Ribes with about 120-150 species. Escallonia and Itea which are sometimes listed as being in the family have been placed in families of their own. Ribes is the genus of the gooseberries (with spines) and currants (without spines). They occupy mostly northern temperate regions with a few species in Central and South America, and are shrubs with simple, alternate, palmately veined and often palmately-lobed leaves, and flowers with 4-5 sepals and petals.
 

The Malvaceae or mallow family is a very complex one which is still in the process of being well defined. The way it is viewed by the two main schools are in a restricted monophylletic sense and in a broader sense. In the former, it is considered to have about 115 genera amd 1500 species, in the latter about 250 genera including lindens, kapoks, baobabs, durians, balsa, cacao and others. The family most closely related to the Malvaceae is the Bombacaceae, which is the family of the silk-floss trees. A typical mallow has five showy petals and numerous stamens fused into a tube around the pistil. The best known of the shrubby genera are Malva, Hibiscus, Abutilon, Lavatera and Althaea, while cotton (Gossypium) and okra (Abelmoschus) are two important agricultural members. The family also contains some trees, and is very widespread with a center of diversity in the American tropics.



The Nepenthaceae is a monotypic family of tropical carnivorous plants containing about 120 species in the single genus Nepenthes. The name is derived from the Greek roots ne- meaning 'not' and penthos meaning sorrow or grief. It was first published in 1737 by Linnaeus and refers to Homer's use of the name Nepenthe in the Odyssey. Nepenthe was a drug which supposedly banished sorrow with forgetfulness, and Linnaeus wrote that all who beheld orchids would be so astonished as to forget all past ills. These plants are commonly referred to as pitchers or monkey cups. The pitcher is a modified leaf arising from a tendril growing out of the stem, and is filled with a watery or syrupy substance in which mostly insects but occasionally larger prey is trapped. Above the pitcher is often a lid which keeps rainwater from diluting the fluid within. Male and female flowers are produced on separate plants.
 

The Bromeliaceae is a large tropical and temperate New World family which is familiar to most people because of its inclusion of such species as pineapples and Spanish moss. There are about 45 genera and some 2000 species in this diverse family, all in the Americas except for one on the west coast of Africa. It was Columbus who encountered pineapples being cultivated in the West Indies, but the Incas, Aztecs and Mayas were well familiar with bromeliads and used them for a variety of purposes. By Linnaeus's time, 14 genera had been named. The family is divided into three sub-families, spiny-leaved terrestrial species, tank bromeliads which can store water in a "tank" formed by their tightly-overlapping leaf bases, and epiphytic species. The family takes its name from the genus Bromelia which was named for the 17th century Swedish botanist Olof Bromol.
 

The Melastomataceae is a very large family containing some 200 genera and 4500 species of herbs, shrubs, trees or lianas. The family is mostly tropical with two-thirds coming from the New World. Leaves are typically arranged in pairs and situated in a decussate fashion, each pair being at a right angle to the pairs above and below. Many members of this family are extremely invasive, and have developed adaptations such as high germination rates, the ability of fragments to root, rapid growth, early maturity, and efficient seed dispersal, allowing them to efficiently colonize secondary areas and disturbed habitats. Miconia calvescens and Clidemia hirta are two species which have caused great damage on Pacific islands. The family name comes from genus Melastoma, and is derived from the Greek melas, 'black,' and stoma, 'a mouth.' The berries of this species stain the mouth black.



The Amaryllidaceae is a large family of perennial herbs usually growing from bulbs with simple, alternate leaves and containing about sixty genera and over 800 species. At one time or another, members of this family have been included in the Liliaceae and the Alliaceae (onion) families, and are closely related to Agapanthus. They are mainly distributed in tropical and subtropical parts of the world. Major regions of diversity for this family are South Africa and South America. The flowers are often large and showy and held at the end of a leafless stem called a scape, and they are frequently utilized in garden plantings. The family was originally described in 1805 by Jean Henri Jaume St. Hilaire and was named in honor of Amaryllis, a lovely shepherdess referred to by Theocritus, Virgil and Ovid in classical times and by the English pastoral poets of the 16th and 17th centuries.
 

The Cannaceae is a monotypic family with only a single genus, Canna, which itself contains some 20 species distributed from southeastern North America through South America. Often called lilies, they are actually closely related to bananas and gingers, with wide leaves arising from rhizomes. Frequently grown in the form of ornamental hybrids, they are among the most extensively grown tropical bedding plants, and hundreds of named cultivars currently exist. The name comes from the Greek word kanna used for a type of reed. C. indica was the first species introduced into Europe and was imported from the West Indies, which accounts for the name 'indica.' The plants have been used as a very rich source of starch, its fibers have been used as a jute substitute and for making paper, a purple dye has been extracted from the seeds, and the plants have been fermented to make alcohol.
 

The Orchidaceae is the world's second largest and most diverse plant families, comprising as it does approximately ten percent of all of the flora on Earth with some 800 named genera and a staggering 25,000+ species as well as at least 100,000+ hybrids and cultivars. Some of the genera which are best known are Paphiopedilum, Cattleya, Epidendrum,Vanda, Cymbidium, Brassia, Phalaenopsis, Spiranthes, and Dendrobium. One that many people do not realize is an orchid is the beautiful Vanilla. The Greek word orchis was first used by Theophrastus and means "testicle", from the appearance of the underground tuberous structures of the genus Orchis. The Orchidaceae is a very old family, possibly dating back to the time of the dinosaurs, but at the same time is considered by many authorities to be an advanced one, among the most highly evolved of the monocots.



The Leeaceae is a monotypic family containing the single genus Leea with approximately 70 species. Leea has often been put in the grape family (Vitaceae ), and derives its name from the 18th century Scottish horticulturist James Lee who was a nurseryman at Vineyard Nursery in Hammersmith, gardener to the Duke of Argyll, and a correspondent of Linnaeus. He had plant collectors both in North America and at the Cape of South Africa. There are species of Leea in South and South-east Asia extending to the Himalayas and Australia, and parts of Africa and Madagascar. They can be herbs, trees or shrubs, and are self-supporting without tendrils as in the Vitaceae. The leaves are alternate and pinnate or rarely simple, and the fruits are rather dry, subglobose berries of purple, black or orange.
 

The Rutaceae is better known to most people as the citrus family. It belongs to a larger group, order Sapindales, which includes soapberries, sumacs, maples, horse-chestnuts, both frankincense and myrhh, and mahoganies. Members of the Rutaceae can be herbs, shrubs or trees, and often have flowers or leaves with strong scents. The genus Citrus is the most important economically, but there are non-citrus fruits such as the white sapote. Other family members are used for medicinal purposes and in the perfume industry. The family contains about 160 genera and approximately 1600 species. Spines are typical in this family, and the flowers are most often pollinated by insects. This is a very widespread family, including temperate, tropical and sub-tropical regions with most genera in southern Africa and Australia.
 

The Hamamelidaceae is a family of shrubs and small trees containing 27 genera and about 80-90 species in the order Saxifragales which includes the peonies, gooseberries and currants, saxifrages, and stonecrops. The family takes its name from the genus Hammelis or witch-hazel, the name having been used by the ancient Greek for a plant called the medlar. An astringent extract of the bark and leaves of this genus is called witch-hazel and is used topically to treat bruises and insect bites. Loropetalum or Chinese fringe flower is a familiar resident of gardens. Species of this family are native to parts of eastern North America, Mexico, eastern Asia, Central America, Africa (including Madagascar), the Pacific Islands, and Australia. Leaves are simple and alternate. Liquidambar or sweet gum is no longer considered part of this family.



The Xanthorrhoeaceae is a family of flowering plants in the order Asparagales, an order which according to the APG System II includes such members as the Alliaceae, Asparagaceae, Iridaceae, Orchidaceae and nine or ten others. Like some other families, it can be viewed in a broader or narrower sense. In the narrow sense, it contains only genus Xanthorrhoea with about 28 species and is limited to Australia, however in the broader sense it includes some three dozen genera that would otherwise be placed in separate families. Genus Xanthorrhoea derives its name from the Greek xanthos, 'yellow,' and rheo, 'to flow,' referring to a resinous yellow gum that can be extracted from the stem. Members of this genus are perennials with arborescent (or underground) stems, thick clusters of basal leaves, cylindrical, spike-like inflorescences and non-fleshy, dehiscent fruit.
 

The Plumbaginaceae, called the leadwort or plumbago family, is in the order Caryophyllales and contains about 24 genera and 800 species. This very large order also includes iceplants, amaranths, cactuses, pinks, sundews, buckwheats, pitcher plants, tamarisks and quite a few others. The family takes it name from genus Plumbago, which comes from the Latin plumbum, 'lead,' and the ending -ago indicating a resemblance or property, reflecting an apparent early belief that the plant could cure lead poisoning. The family is widespread and cosmopolitan, ranging from arctic to tropical regions, but particularly likes dry places with saline soils like salt flats and seacoasts. The basal leaves have glands that can excrete calcareous salt crystals. Members of this family are typically herbaceous or small shrubs with a few lianas, mostly perennial, and a few are used for medicinal purposes.
 

The Bignoniaceae is a very widespread family of herbs, shrubs, trees and lianas in the tropical, subtropical, and temperate Old and New Worlds. Commonly called the trumpet vine or trumpet creeper family, it contains about 110 genera and 650 species. It gets its name from genus Bignonia, itself named in honor of Abbé Jean Paul Bignon who was librarian to King Louis XIV, and some of the well-known members of the family are Tecoma, Catalpa, Tabebuia, and Jacaranda. Many species are important ornamentals and have large and spectacular flowers. Leaves are typically opposite or whorled and pinnately or multiply compound. Trees of Tabebuia and Catalpa are important timber sources. The common landscaping tree Jacaranda includes about 49 species in the Neotropics. The Bignoniaceae is in the order Lamiales with mints, verbenas, olives and figworts.



The Magnoliaceae is a family of about 200 species of trees and shrubs that usually have large flowers. Certain of the features of this family indicate that it is a fairly primitive one. Among these features are the lack of differentiation between sepals and petals, and the arrangement of stamens and pistils in spirals on a conical receptacle rather than in rings. There are fossilized specimens identified as being in this family dating back almost 100 million years. It is a very widely spread family, ranging from North and Central America, the Caribbean and tropical South America all the way to India, Indochina, China, Japan and Korea. Alternate, simple, petiolate leaves are characteristic of the family, and many species have fragrant flowers. Magnolia is the largest genus and is named after French botanist Pierre Magnol. Magnolia grandiflora is the state tree of Mississippi.
 

The Ericaceae is known as the heather or heath family. It is a huge family with some 125 genera and as many as 3,500 species, and is present mostly in temperate regions from all over the world except Australia. Members of this family typically have woody stems, simple and alternate leaves, and flowers with 4-5 petals, but they can also have opposite and needle-like leaves They are also usually found in acidic soils and are dependent on fungal mycorrhiza. Bogs and moors are places where heathers are often found. The flowers of many species look like little bells, and pollination is generally by insect or wind. Some of the more notable genera are Arctostaphylos (manzanita), Rhododendron (azaleas and rhododendrons), Erica (heath), and Vaccinium (cranberries, huckleberries and blueberries). Most of the Rhododendrons are from China and most of the Ericas are from South Africa.
 

The Myrtaceae or myrtle family contains as many as 3000 species in 130-150 genera. All species are woody and have floral parts in fours or fives. They range throughout the world's tropical and subtropical regions and make up a large part of the tree and shrub population of Australia. The evergreen leaves are simple, and mostly opposite and entire-margined. Most species have numerous brightly colored stamens, leaves having essential oils and strongly-scented, and fruits typically either capsules or fleshy berries. Some of the more well-known members of the family are Eucalyptus, allspice, Surinam cherry, the bottle-brushes, guavas and cloves. In areas where these species are native, there are parasites which have evolved to attack the leaves, but in the United States, which is outside the natural range of the Myrtaceae, cultivated plants are gener-
ally pest-free. Oils extracted from the leaves had had medicinal uses.



The Anacardiaceae is also called the sumac or cashew family. It contains approximately 80 genera and about 600 species in mostly tropical regions but extending into temperate zones of both North America and Eurasia. In this family flowers are typically 5-merous, small and arranged in clusters. Stems and leaves often contain resinous compounds or strong-smelling volatile substances. Urushiol, a skin irritant which is produced in the genera Toxicodendron and Metopium, is probably the best known of these, causing rashes and blisters. Poison sumac, a species of Rhus, also contains urushiol. These secondary compounds probably evolved as a defense against herbivore and insect predators. A number of economically important species are in this family, including cashews, mangoes and pistachios, and another familiar member is Schinus (the pepper trees).
 

The Fabaceae is the family that used to be called the Leguminosae, and is the bean, pea or legume family. The name comes from the genus Faba, which is now part of Vicia. It is the third largest family after orchids and sunflowers, and contains over 700 genera and almost 20,000 species. It is divided into three sub-families which are treated as full families by some, MimosoideaeCaesalpinoideae, and Faboideae. Leaves are typically alternate and pinnately compound, although many are trifoliate or palmately compound. Flowers are made up of five usually fused sepals and five free petals. Most commonly the fruit is a legume which is a pod that opens along a lengthwise seam. The Fabaceae is one of the most economically important plant families in the world, and has long been closely associated with the development of human societies.
 

The Fagaceae, commonly called the oak or beech family, contains nine genera and about 900 species. It is widespread in the northern temperate regions and also extends into the tropics in Central America and southeast Asia. Nothophagus or southern beech formerly was included as the only southern hemisphere genus in the family but it has now been put into a family of its own. Quercus (oak) is a well-known member of the family, and another is Castanea (chestnut). You have to know what you're looking at to recognize the flowers of this family or even to tell that it has them. Female flowers are small and inconspicuous, while the male ones are in clusters of dangling catkins. The leaves are simple, alternate and have deciduous stipules, and the fruits are nuts which are usually called acorns. Many family members produce valuable lumber.



The rose family or Rosaceae is a large and very popular family of flowering plants containing over a hundred genera and between 3,000 and 4,000 species, primarily but not exclusively inhabiting northern temperate regions. The structure and makeup of the family is still under study. This is a very diverse family and it's difficult to describe features that apply to all members. In size they vary from herbs to shrubs to trees, leaves are usually alternate, simple to pinnate or palmate, the flowers are almost always perfect (having both stamens and carpels), regular (radially symmetric), and contain many stamens, usually more than twice the number of petals. The fruits are of various types. This is an important economic family, including such fruit crops as blackberries and raspberries, strawberries, apples, pears, almonds, apricots, cherries, peaches and plums.
 

The Caryophyllaceae is a large family with about 80 genera and 2000 species. It is commonly called the carnation or pink family. This is a primarily temperate region family with a few members growing toward the tops of tropical mountains. The greatest diversity of this family is in the Mediterranean. Almost all are herbaceous with only a few being shrubby. Leaves are simple, entire and mostly alternate, the flowers are regular and almost all perfect, and the fruits are capsules or achenes. Typically the petals are notched, toothed, fringed or lobed in some fashion. This is a family of mostly ornamentals, wildflowers and weedy species, with Dianthus (the carnation) being probably the most important economically. Other familiar members are baby's breath, catchflies and campions, bouncing bet, chickweeds and sand spurreys.
 

The Lauraceae or laurel family is a group almost entirely composed of shrubs and trees with simple leaves usually punctate and strongly-scented. Rather than petals and sepals, laurel flowers have sepaloid tepals in 2 whorls of 3 each. The fruit is a berry or drupe. This family contains 30-
50 genera and about 2000 species that are widespread and common in tropical and subtropical regions of the world. A few genera extend into temperate areas such as sassafras, spicebush and bay laurel in the U.S. They are particularly common in Brazil and southeast Asia. Cinnamon, bay leaves, avocados and camphor are a few of the products produced by laurel family members, as well as the flavoring sassafras which has been used widely in herbal teas. Perfumes have been made from the oils contained in laurel leaves, and many of the trees are considered as valuable timber woods.



The Clusiaceae is a family of trees and shrubs containing about 50 genera and 1200 species. It was formerly known as the Guttiferae, and is commonly called the mangosteen family. The family name honors the celebrated French botanist Carolus Clusius, aka Charles de l'Écluse. The family is widespread in the tropics and in northern temperate regions. The large genus Hypericum or St. John's-
worts is in a sub-family that is sometimes treated as a family of its own. The leaves are opposite or whorled, simple, usually entire and often glandular-punctate. The flowers have 4-5 sepals, 4-6 petals and 9-many stamens. The fruit is usually a capsule or a berry. Tropical members of the family produce lumber, drugs, dyes and gums and edible fruits such as the mangosteen. Many species contain a milky sap. Other members of the order Malpighiales include violets, willows, mangroves, flax and passion-fruit.
 

The Verbenaceae, commonly known as the verbena or vervain family, contains around 90 genera and between 2000 and 2600 species. The family includes trees, shrubs and herbs, and is pantropical with a few temperate species. It is closely related to the Lamiaceae or mint family and like them often has square-shaped stems and aromatic foliage. The leaves are mostly simple and opposite or whorled. The family takes its name from the genus Verbena, a Latin name for a plant sacred to the Romans. Typically species have 5 connate sepals and petals and the fruit is usually a drupe or occasionally nutlets. Lemon verbena has been grown for flavoring, teak is a valuable lumber, and verbena itself has had medicinal uses. There are many species that are beautiful ornamentals, while others are weedy. Some genera have been transferred to the Lamiaceae, and others to families of their own.
 

The Sterculiaceae is also known as the cacao family. It is a mostly tropical and subtropical family with 65 genera and 1000 species and takes its name from the genus Sterculia, which is named in turn from the Latin stercus, "dung or manure," from the unpleasant smell of the flowers and leaves of some species. The family is composed mainly of shrubs and trees with simple, alternate leaves and flowers with five connate sepals and five or zero petals. As is the case with other families, a revision is likely in the works for Sterculiaceae and its close relatives Tiliaceae and Bombacaceae. Some systematists place the Sterculiaceae into the larger family Malvaceae. Many of the species in this family yield valuable lumber, and its best known products are chocolate and cocoa from Theobroma cacao and kola nuts from the genus Cola. Other familiar genera are Brachychiton and Fremontodendron.



The Convolvulaceae, commonly called the bindweed or morning-glory family, is a cosmopolitan family of 50-65 genera and about 1500 species. Most people have a good idea of what morning-glories look like, with their climbing or twining stems and their large 5-lobed and funnel-shaped flowers that are structured like the aperture of a camera and unravel as they open. The leaves are alternate and simple and many species have a milky sap. The Convolvulaceae is mostly a herbaceous family with some shrubs and trees, and takes its name from the Latin convolvere, "to wind," in reference to the winding character of the stem. The sweet potato (Ipomoea batatas) is a member of this family, and the seeds of some species have had medicinal uses as purgatives. Bindweed is usually a troublesome weed. The parasitic dodder has been considered by some taxonomists as a family member.
 

The Papaveraceae, or poppy family, is a mostly herbaceous family with a few shrubs and small trees occurring in temperate and subtropical climates. The family contains about 26 genera and 250 species and takes its name from genus Papaver. Many species produce a milky latex. The leaves are simple, alternate or whorled, and usually lobed, pinnatifid, or much-divided. The flowers are either
solitary or in cymes or racemes, and are usually fairly large and showy. There are many stamens arranged in spiral whorls. Most of the species contain alkaloids and many are poisonous. Some poppies are well-loved like the state flower of California (Eschscholzia) and P. rhoeas invoking the memory of Flanders Field, while others such as the opium poppy (P. somniferum) have a different reputation. The two main areas of distribution for this family are western North America and eastern Asia.
 

The Poaceae is the world's fifth largest plant family, exceeded in numbers of species only by the Asteraceae, Orchiaceae, Fabaceae and Rubiaceae. It was formerly known as the Gramineae and is known to everyone as the grass family. It contains about 600 genera and between nine and ten thousand species. Grasslands comprise 20% of the vegetation cover of the earth, and the Poaceae with food grains, forage grasses and bamboos used in construction is without question the most important of all plant families to human economies. Just three cereal grains (rice, wheat, and maize or corn) provide more than half of all calories eaten by humans, and 70% of all crops are grasses. Barley, oats, rye, millet and sugar cane are other major agricultural crops. Grasses are quite different from other plants, with very distinctive features that require learning a whole new set of botanical terms.



The Asteraceae or sunflower family is the world's 2nd largest plant family. At one time it was called the Compositae, and this is a clue as to the essential character of the family. What appears to be a single flower is actually a flowering head made up of many ray flowers around the rim and many disk flowers in the center. Some species have no ray flowers and some species have no disk flowers. But all have either both or one or the other. So the flowers are composites, that is, made up of distinct parts. The fruits of the Asteraceae are a specialized type of achene. The family contains more than 1600 genera and around 23,000 species, and is sometimes called the aster family after one of its main members. The largest genus is Senecio with 1500 species. It is mainly a herbaceous family but does include a few trees and climbers. The family is likely about 50 million years old and is worldwide.
 

The Onagraceae, commonly called the willowherb or evening primrose family, contains around 20 genera and 650 species. This is a widespread family of trees, shrubs and herbs ranging from boreal regions to the tropics. It takes it name from the genus Onagra, which is now Oenothera. The typical pattern in the evening-primroses is to have four sepals and four petals, but in some genera such as Fuchsia the sepals are as brightly colored as the petals and thus gives the impression of having eight petals. One genus, Ludwigia, is 5-merous, while Circaea is 2-merous. This family is especially well represented in western North America, and includes many very showy wildflowers. The name evening-primrose refers to the time of day when the flowers are open, but this applies mainly to Oenothera which is pollinated by night moths. Most other members are open during the day.
 

The Scrophulariaceae or figwort family, often just called scrophs by botanists, is a large family of herbs and shrubs containing around 275 genera and 5000 species, and inhabiting areas from sea level to the tops of mountains from wetlands to deserts in mostly temperate areas. Currently the family is in a state of revision due to molecular studies, and may be radically different in the near future. The flowers have 5 sepals and 5 petals and the corolla is bilabiate. The fruit is most often a capsule and occasionally a berry. The family takes it name from genus Scrophula which in turn was named in 1474 by an Italian physician who noticed the resemblance between the rhizomal knobs of some species and the tubercular condition of human lymph nodes called scrophula. Some species in this family are root parasites like Castilleja and Orthocarpus, and the family includes monkeyflowers, snapdragons and paintbrushes.



The Lamiaceae, or mint family, contains about 200 genera and 3500 species of mostly herbs, some shrubs, and a few trees and climbers. It was known at one time as the Labiatae because the flowers typically have petals fused into an upper lip and a lower lip, but now takes its name from genus Lamium. This is a family that is familiar to most people due to its aromatic qualities and because it includes such important herbs as basil, mint, rosemary, sage, savory, marjoram, oregano, thyme, and lavender. It is a close relative of the vervain family and some phylletic revision is underway. The leaves are opposite and decussate or whorled, the stems are frequently square in cross section, and the flowers are bilaterally symmetric with five united petals and five united sepals. Some other members familiar to most people are coleus, chia, and catnip. Aromatic oils are also utilized in the perfume industry.
 


The Asphodelaceae or asphodel family is one like many other families that is under revision. Its main genus is Aloe, which was placed by Cronquist as a family with the lily, iris and agave families into order Liliales. The 1998 APG system accepted the Asphodelaceae as a family in its own right, but the 2003 APG revision made this taxa an optional segregate of the
family Xanthorrhoeaceae in the order Asparagales. This is why aloes sometimes are listed in the Liliaceae, Agavaceae or Asphodelaceae. The greatest diversity of the putative Asphodelaceae is in South Africa with such genera as Aloe, Asphodelus (hence the family name), Gasteria, Haworthia, Bulbine, Kniphofia and others, and about 800 species. The leaves are mostly basal or subbasal, linear, parallel-veined and sometimes succulent. The perianth parts are in 3's and the fruit is a capsule. One genus is in New Zealand.
 

The Aquifoliaceae or holly family is a small family with only a single genus, Ilex, but that genus contains about 600 species of woody shrubs and trees distributed almost worldwide with the exception of Australasia and western North America, and rare in Africa. The family takes its name from Aquifolium, which was the classical name for the holly. The leaves in this family are typically alternate, simple, stipulate and often spiny-margined or toothed. The flowers are in various types of inflorescences, but are all radially symmetric with 4-7 distinct or basally connate sepals and petals. The fruits are drupes or berries. Most of the family members are evergreen but some are seasonally decidious, and most species are pollinated by insects, most commonly bees. Fossil pollen identified as holly has been found dating back to the Upper Cretaceous period. The red berries makes them popular ornamentals.



The Crassulaceae or stonecrop family is a medium-sized family which has representatives everywhere except Australia and the islands of the western Pacific. It contains between 1200 and 1400 species in about 35 genera. Its greatest center of diversity is South Africa, and its major characteristic is its succulent foliage which is designed to store water in dry and or cold areas. Many of the family members have wierd appearances, and are quite popular in the horticultural trade and in home landscaping. The largest genus is Sedum which inhabits mostly temperate areas and tropical mountains. Crassula ovata (aka jade plant) is one of the best known family members. Because they often are native in stony soils, they are especially well suited to rock gardens. The flowers though small are often quite lovely. Other familiar members are Dudleya, Aeonium, and Echeveria. They have little economic importance.
 

The Oleaceae or olive family is a family containing 24 genera and 600 species of woody plants including shrubs, trees and lianas. The family is particularly well represented in temperate and tropical Asia, and other members inhabit southern Europe, North and South America, Australia and Africa. It is an economically important family with one of its major members being the common olive, Olea europea, from coastal areas of the eastern Mediterranean region. The olive is one of the most referred to plants in all of recorded literature producing much consumed fruit and olive oil, but in South Australia it has become a major invasive weed.The leaves of this family are usually opposite and simple, but sometimes are pinnate-compound. The typical pattern is for the flowers to have 4 united sepals and 4 united petals. Other familiar family members are forsythia and the ashes, jasmines and ligustrums.
 

The Proteaceae or protea family is a fairly large and variable family mainly restricted to the southern hemisphere. Most family family members seem to prefer acidic, well-drained and nutrient-depleted soils. The family contains about 80 genera and perhaps as many as 2000 species, and is in the order Proteales with the superficially dissimilar family Platanaceae. These are mostly evergreen trees and shrubs and the typical inflorescense is showy and composed of many small densely-packed flowers. South Africa and Australia are the two main centers of diversity, with Protea, Banksia, Grevillea, Hakea, Leucadendron, Leucospermum and Macadamia being the major genera. Many family members have specialized roots growing at ground level which maximizes water and nutrient absorption. Except for the macadamia nut, the Proteaceae family does not produce much of commercial significance.



The Euphorbiaceae or spurge family is a large mostly herbaceous family including about 240 genera and some 6000 species. It is fairly widespread from tropical regions of India, Southeast Asia, Africa and America, and non-tropical areas such as the Middle East, the Mediterranean, South Africa and the southern U.S. It is also an amazingly diverse family with species ranging from tiny ground-hugging plants to giant cactus-like succulents. The largest genus is the one that gives the family its name, Euphorbia, with around 2000 species. This genus was named for Euphorbus, the Greek physician of Juba II, King of Mauretania. This genus is characterized by an inflorescence called a cyathium, which is a flower cluster containing unisexual, apetalous male and female flowers. The leaves are mostly alternate and simple, but occasionally are palmately compound. Many family members contain a milky sap.
 

The Rubiaceae, commonly called the coffee, bedstraw or madder family, is the fourth largest flowering plant family after the Orchidaceae, Asteraceae and Fabaceae. It includes some 600 genera and about 10,000 species with a cosmopolitan distribution which is concentrated mainly in the tropics and subtropics. Despite its large size, the names of most genera in the family are not particularly recognizable but some of the more familiar ones would be Gardenia, Coffea (the source of coffee), Cinchona (the source of quinine), and Galium (bedstraw). Most family members are trees and shrubs. The leaves are simple and usually entire, mostly opposite with some whorled. The family takes its name from genus Rubia, an epithet derived from the Latin ruber or "red," for a reddish dye present in the roots. The corollas are typically sympetalous and 4-5-lobed, and the ovary nearly always inferior.
 

The Moraceae or mulberry family takes its name from genus Morus, an epithet derived from the Latin morum for a mulberry. It is a family with about 40 genera and 1000 species mainly concentrated in tropical and subtropical regions. The best known of its members is Ficus, the genus commonly referred to as figs or banyans. Breadfruit is another familiar member. Most are trees and shrubs, and nearly all have milky sap. The leaves are simple and mostly alternate. The flowers are minute and usually densely aggregated. In Ficus, the receptacle is spherical with a single opening at the distal end, and the interior of what appears to be a fruit contains hundreds of tiny unisexual flowers. Well-known species of Ficus include carica (the edible fig), benghalensis (bengal fig), elastica (rubber tree), microcarpa (the Indian laurel), pumila (creeping fig) and several species known collectively as strangler figs.



The Cornaceae or dogwood family is another family about whose taxonomy there is much disagreement. Apparently including from 1 to 6 (some say up to 15) genera and up to 60 species, its main member is Cornus. Several genera have been removed from the family and now placed in families of their own. According to some sources, genus Cornus has either been broken up into as many as 12 genera, or these genera have been lumped together under Cornus. The family contains mostly trees and shrubs, and is mainly concentrated in the northern temperate regions with some in tropical Asia, and a few in South America, Africa and Australia. It is closely related to the Hydrangeas. Leaves are usually simple and entire, the inflorescences are terminal with regular flowers sometimes subtended by showy white bracts, and fruits are drupaceous and fleshy. Many species are cultivated as ornamentals.
 

The Liliaceae or lily family was formerly considered to contain many genera that have now been moved into families of their own, such as Alliaceae, Agavaceae, Amaryllidaceae, Hyacinthaceae, Asparagaceae and others. More recent circumscriptions have limited the family to from 16 to 60 genera and about 650 species. This is very different from the 280 genera and 4000 species that it was once said to include. Lilies are monocotyledons with linear, mostly parallel-veined leaves and flower parts in threes. The family is mainly distributed in the northern temperate zones with a few genera reaching the subtropics, and includes some of the oldest known ornamentals of the western world. Some of the familiar genera are Lilium (from which the family takes its name), Tulipa, Crinum, Fritillaria, Chlorophytum and Zygadenus. Fruits are typically loculicidal capsules, but in some genera like Clintonia is a berry.
 

The Lythraceae or loosestrife family is a medium-sized family of 32 genera and about 600 species mainly located in the tropics but extending into some temperate regions. It takes its name from genus Lythrum, an epithet derived from the Greek lythron, "blood," alluding to the color of the flowers. The name loosestrife refers to an old belief that this herb could quell the unruliness or strife of oxen when yoked, and it apparently does have the affect of keeping flies and gnats away. It is a mostly herbaceous family with some shrubs and trees. The leaves are typically opposite, simple and entire, and the flowers range from being radially symmetric to zygomorphic and are usually brightly-colored with 4-6 petals and twice as many stamens as sepals. The family is closely related to the evening primroses and includes such species as pomegranates, the water chestnut, the dyeplant Henna, and the crepe myrtles.



The Solanaceae, nightshade or potato family, derives its name probably from the Latin sol or solis, "sun," from the perceived resemblance of some of its flowers to the sun and its rays. It contains about 85 genera and between 2000 and 4000 species depending on how its circumscription is viewed, and it includes many very familiar species such as eggplant, belladona, peppers, jimsonweed, potatoes, tobacco, tomatoes, mandrake and petunias. Many species in this family have evolved alkaloids presumably to protect them from animal predators, and these alkaloids in some cases are beneficial to humans and in others poisonous. The flowers are typically funnelform with five fused petals, the leaves are alternate, and the fruits are either berries or dehiscent capsules. Alkaloids in the family include scopolamine, atropine, nicotine and the less well known by name but oft experienced capsaicin (in peppers).
 

The Arecaceae or palm family is a monocot family containing some 200 genera and between 2000 and 2500 species distributed mainly in the tropical regions of Central America, northern South America and East Asia. The most familiar image of palms is the large, com-
pound, evergreen leaves arranged at the top of an unbranched stem, but they are actually morphologically quite diverse. Palms include woody shrubs, vines and trees, the leaves of which are alternate and palmately or pinnately cleft. The flowering inflorescences are usually paniculate with small and radially symmetrical flowers. and the fruits are usually drupes. Palms are one of the most recognizable and widely cultivated plant families in the world. Madagascar has one of the highest diversities with more species than is present in continental Africa. Palms have been cultivated for more than 5000 years and produce many very useful items.
 

The Apocynaceae or dogbane family is commonly so-called because of its toxic nature. The name Apocynum originally applied to a plant that was supposedly poisonous to dogs. The family at present includes about 425 genera. The number of species varies greatly from 1500 to 6000 depending on the source. They are spread widely across tropical and subtropical areas, and a few genera even extend into temperate zones. Some of the more familiar members are oleander (Nerium), frangipani (Plumeria), periwinkle (Vinca), Natal plum (Carissa), and now that this family has been placed in with the Apocynaceae, the milkweeds (Asclepias). Milky sap is a general characteristic of most members of the family. The leaves are usually simple and opposite sometimes whorled, and the flowers typically contain five at least partially fused petals. The fruits are follicles, capsules, or berries.



The Polygonaceae or buckwheat family takes its name from Greek poly, "many," and gonu, "knee," referring to the many swollen node joints that some species have. The family includes about 45 genera and some 1100 species. Just three genera, Eriogonum, Polygonum and Rumex, together account for 650 species. The majority of members are perennial herbs. The leaves are simple, almost always alternate, and usually stipulate, and the flowers are small and radially symmetrical with two undifferentiated whorls of 3-6 distinct or basally connate tepals. The fruits are usually 3-angled achenes. The crop species of buckwheat is the Eurasian genus Fagopyrum, while in North America the genus Eriogonum is referred to as wild buckwheat. Despite the name and the grain-like use of buckwheat, it is not a grass and is not related to the grasses. Many species are weedy invasives.
 

The Chenopodiaceae or goosefoot family contains about 100 genera and 1500 species distributed worldwide but concentrated mainly in desert, semidesert and saline areas of the Old World. Recent circumscriptions of this family such as APG and APG II place it into the Amaranthaceae on the basis of molecular studies. Most species have flowers that are tiny and hardly recognizable as such. The leaves are usually simple and entire, alternate or opposite, sometimes thickened or succulent, often with mealy texture or glandular hairs. Some genera such as the pickleweeds lack leaves altogether and their photosynthesis takes places in the succulent green stems. The perianth consists of undifferentiated 5-lobed tepals. The family includes a number of commercially very significant members such as beets, sugar beets, spinach, chard, and quinoa, a staple in the Andes region for its edible leaves and seeds.
 

The Campanulaceae or bellflower family includes about 70 genera and 2000 species of mostly herbs and shrubs with milky sap. The family has a widespread distribution from the arctic to the Southern hemisphere and excluding only the manjor deserts. In addition to the many herbaceous species, the family includes some climbers and a few small trees. The leaves are typically alternate, sometimes opposite, and are simple and estipulate. The family's common name describes the relatively large and showy bell-shaped flowers that are usually 5-merous and more often than not of some bluish color. The fruit is usually a capsule or a berry. Of all the genera, probably those that are best known are Campanula and Lobelia. Their beauty has made them popular in the horticultural trade, but they have little other economic importance except for some alkaloids present in the sap.



The Calycanthaceae, commonly called the spicebush or sweetshrub family, contains only four genera and about 11 species. It is in the order Laurales, a fairly ancient order with highly diverged morphology comprising seven families including the Calycanthaceae and the Lauraceae (laurel family). This family includes small trees and shrubs that bear essential oils and have opposite, leathery leaves and medium- to large-sized flowers that are solitary and terminal on short shoots. The flowers range in color from white to red and have undifferentiated perianth parts called tepals. The members of the family are distributed in temperate to sub-tropical. Eastern Asia and North America. All species have aromatic bark, and fragrant flowers are also common. Some Calycanthus species are grown for their ornamental value, and some contain an alkaloid similar to strychnine that is toxic to humans.
 

The Polygalaceae or milkwort family contains about 1000 species in 20 genera distributed almost worldwide but absent from New Zealand and other southern Pacific islands and the very Northern Hemisphere. It is in the order Fabales with its sister family Fabaceae. The family is composed of mainly herbs and shrubs, with a few trees and climbers. Over half the family members are in the genus Polygala, which derives its name from the Greek polys, "much," and gala, "milk." It was so named because it was thought originally (and incorrectly) to stimulate breast milk and not because it contains milky sap. The leaves are simple, estipulate and usually alternate, and the flowers are usually zygomorphic and often share a resemblance with the legumes, with corollas typically of 3 petals, the median anterior of which is keel-like and sometimes with a fringed crest. Used in local medicines.
 

The Cucurbitaceae or gourd family is a family of major food plants such as cucumbers, melons, squashes, gherkins, gourds, pumpkins and zucchinis. It is highly specialized and contains about 825 species in 125 genera distributed mainly around the tropical regions of the world. Members with edible fruits were among the earliest cultivated plants in both the Old and New Worlds. Most species are climbers with swollen tuberous rootstocks underground but the family also includes shrubs and even some trees. The typical type of flower is large, 5-merous, radially symmetrical and either yellow or white, with petals that are often united at the base. The leaves are alternate and usually coarsely hairy. The fruit is most commonly a type of fleshy berry called a pepo or gourd, sometimes an explosively dehiscent dry capsule. The Cucurbitaceae family is in the order Cucurbitales along with the Begoniaceae.



The Dipsacaceae or teasel family is native to most temperate areas of the Old World and centered in the Mediterranean region but extending from the Canary Islands to Asia and southward to South Africa. It contains about 250 species in 10 genera, and according to APG II is placed in the order Dipsacales with the honeysuckle and valerian families. Scabiosa is another familiar genus. Family members are primarily herbaceous with some low shrubs. The leaves are opposite or in a basal rosette, and the flowers are in dense involucrate and bracteolate heads, the calyx 4- or 5-
merous and often represented by five or up to ten pappus-like bristles, and the corolla is tubular or trumpet-shaped with 4 or 5 lobes either regular or 2-lipped. The receptacle in Dipsacus is elongated. Inflorescence and calyx characters are strikingly variant probably due to dispersal mechanisms of the indehiscent fruits.
 

The Acanthaceae or acanthus family is fairly large with some 2500-3000 species in about 250 genera. The family is known from a variety of very diverse tropical and subtropical habitats, and its four main centers of distribution are Indo-Malaysia, Africa, Brazil and Central America. It is composed of mainly annual and perennial herbs, shrubs and climbers, but also includes some large trees. The leaves are simple, opposite, estipulate and usually entire-margined, and the flowers are in spikes, racemes or cymes. Large and showy involucral bracts are fairly characteristic with tubular corollas that are 2-lipped or 5-lobed. The fruits are dehiscent capsules. Some of the familiar genera in addition to Acanthus are Justicia, Thunbergia, Ruspolia, Barleria and Ruellia. Many species are popular ornamentals and others like zebra plant and nerve plant are commonly grown as house plants.
 

The Ebenaceae, commonly called the ebony family, contains only two genera, Euclea and Diospyros, both of which are large and together include about 500 species. The family is placed according to the APG II system into order Ericales with the families Ericaceae, Myrsinaceae, Fouquieriaceae, Polemoniaceae, Primulaceae and about 20 others. It is distributed in the lowland tropics and subtropics, with a few warm-temperate deciduous species, and is comprised mainly of trees and shrubs. The leaves are typically alternate, simple and entire, and the inflorescences are short and determinate in the leaf axils. Family members generally produce dioecious plants with tubular corollas that have lobes equal to the number of sepals. A persistent, often enlarged calyx on the fruit is a characteristic of this family. The hardwood ebony and the edible persimmon are the two most significant economic products.



The Portulacaceae or purslane family has nearly a worldwide distribution, and although its major diversity is in the southern hemisphere it is also represented in North America and Eurasia. The family contains 20-30 genera and about 500 species of trees, shrubs and herbs, and is currently placed in the same order as the cacti, iceplants, buckwheats, tamarisks, and most carnivorous plants. The leaves are usually simple and entire-margined, often fleshy, glabrous or sometimes with hairs or glandular barbs. The flowers are typically radially symmetrical and are either solitary or in terminal racemes or cymes. The fruit is usually a circumscissile or loculicidal capsule. Many family members are found in arid or semiarid conditions like Portulaca and Calandrinia. Common purslane (P. oleracea) is a widely eaten but not commercially grown vegetable. Other family members are cultivated as ornamentals.
 

The Araliaceae is commonly called the ginseng or aralia family, and includes between 50 and 70 genera and from 700 to 1450 species, depending on which source is consulted. Although primarily a tropical family, its members are distributed throughout much of the temperate world as well. Composed mainly of trees and shrubs, usually evergreen, its species are characterized typically by alternate, often large, pinnately- or palmately-compound leaves and smallish, radially symmetrical flowers in umbels, racemes, heads or spikes. The fruits are berries or drupes. The family is closely related to the Apiaceae (carrot family) and has been placed with them into order Apiales along with the pittosporums and half a dozen other families. The most important economic product of the family is ginseng but others are Chinese rice paper and various medicinal extracts. The ivies are also members of this family.
 

The Apiaceae or carrot family is also called the Umbelliferae, and that name is a clue to the characteristic simple- or compound-umbellate inflorescences that are present in the majority of species. Other species have inflorescences of dense heads (Eryngium) or of racemes or panicles (subfamily Mackinlayoideae). The Apiaceae appears to have been the first flowering plant family to be recognized as such, in the late 16th century. Found all over the world, its members are most common in temperate areas. The family contains 400-450 genera and about 3500 species, including such popular edibles as cumin, parsley, carrot, dill, caraway, fennel, celery, coriander, parsnips, anise and chervil. The leaves are alternate and almost always variously pinnate. The flowers follow a simple pattern of 5 petals, 5 free stamens, reduced calyx and inferior ovary. Poison hemlock is another family member.



The Geraniaceae or geranium family is widely distributed but concentrated in temperate areas. It is absent from the wet tropics and much of Australasia. The family is made up of 5-6 genera and about 800 species of annual and perennial shrubs, herbs and geophytes. The leaves are alternate, usually stipulate, and usually lobed or otherwise divided. The flowers are radially symmetrical (Geranium) or slightly zygomorphic (Pelargonium), with 5 free petals and 5 sepals either connate or united at the base. The inflorescences are usually umbellate or cymose. The fruit is a dry schizocarp made up of five (or three) fused carpels. Genus Pelargonium has about 280 species with a center of diversity in the Cape region of South Africa. It is an important horticultural plant the oils of which are also used in perfumes and flavorings. Other Geraniums have been used in traditional medicines.
 

The Cactaceae or cactus family is one of the more recognizable plant families, although the African euphorbias are often mistaken for cacti. The Cactaceae is re-
stricted to the New World with a single exception, Rhipsalis baccifera, which grows in Africa, Madagascar and Sri Lanka, however it's possible that that species originated in the New World since it exists there as well. Cacti are residents of deserts and semi-deserts, and the family contains about 2000 species in about 100 genera. They are succulent plants adapted to extremely hot and dry environments, their stems containing the chlorophyll they need to produce food, and the leaves having evolved into spines for protection from predators. The flowers are generally large and radially symmetrical. Cacti are a relatively recently evolved family since the continents moved apart, and many have important commercial uses.
 

The Bombacaceae, variously referred to as the bombax, kapok or silk cotton family, is a taxa not recognized at the family level by the APG I and II system and others, but is by many other references. It is closely related to and considered part of Malvaceae by APG. As circumscribed by Heywood et. al., it includes 25 genera and about 250 species of deciduous trees most with swollen trunks. The leaves are alternate, entire and palmately-lobed to compound. The flowers are mostly actinomorphic and showy with 5 petals joined at the base. Known mainly as emergent trees, they are fibrous-barked and sometimes spiny. Ceiba pentandra is one of the tallest trees in Africa. The fruits are often dehiscent, producing the cottony floss when open. Economic products of this family are the lightweight spongy wood balsa, kapok used in life jackets, and spices. Many species are grown as ornamentals.



The Ranunculaceae or buttercup family contains about 2500 species in 50-60 genera inhabiting all continents except Antarctica and ranging from sea level to high altitudes, but being concentrated in temperate and cold regions of both hemispheres. It is also called the crowfoot family probably because of the palmately lobed or compound leaves, and it is represented by annual and perennial herbs, shrubs, lianas and aquatic plants. The inflorescences are terminal, and the flowers either solitary or more commonly in racemes or cymes, showy, and radially symmetrical, although in some genera they are zygomorphic. The perianth consists of one or two whorls that are often not clearly differentiated into calyx and corolla. Some family members are used in herbal medicines. The largest genera are Ranunculus (600 sp.), Delphinium (365), Thalictrum (330) and Clematis (325).
 

The Boraginaceae or borage family has about 2700 species in 150 genera and is comprised of trees, herbaceous plants and shrubs. The tree genera are distributed across the world in tropical and subtropical regions, while the herbs are present almost everywhere although concentrated mainly in the Mediterranean and warm temperate Asia. Another family in taxonomic limbo, the APG system includes the Hydrophyllaceae, which Heywood considers a natural family, and others have broken the Boraginaceae into several families. Vegetative parts are typically stiff-haired, and the flowers are in terminal or axillary cymes or solitary. The fruit is most often a schizocarp that splits into four 1-seeded nutlets. Economic uses of family members include edible fruit, timber, dyes, and medicines. Some of the more well known plants are borage, comfrey, heliotrope, forget-me-nots, popcorn flowers, and fiddlenecks.
 

The Sapindaceae or soapberry family takes its common name from the mildly toxic glycosids with soap-like characteristics contained in the vegetative parts of many its members. The family contains about 2000 species in 150 genera, is distributed everywhere across the world except for the far north and south, and is made up mainly of trees and lianas with some herbaceous plants. Leaves are of various types, usually but not always alternate and often large. The typical inflorescence is a panicle of actinomorphic or zygomorphic flowers, usually small and not showy. Heywood (2007) has put the Aceraceae (maples) and Hippocastanaceae (buckeyes) into this family, which is also related to the citrus fruits, mahoganies and sumacs. Economic products are lychee nuts and rambutans, soaps, valuable timber, and caffeine drinks, and the stems of climbers have been utilized as rope and for fish poison.



The Passifloraceae or passion flower family contains between 500 and 700 species in about 16 genera and has a mainly tropical and subtropical distribution with a few species reaching more temperate areas. The family includes trees, shrubs, woody or herbaceous climbing plants, and annual and perennial herbs. The family takes it name from the genus Passiflora, an epithet derived from the Latin passio, "passion," and floris, "flower." In the 15th and 16th centuries Spanish missionaries discovered the flower and made it the symbol of the crucifixion of Christ, the radial filaments representing the Crown of Thorns, the ten petals and sepals representing the ten apostles, and the five lower anthers representing Jesus' five wounds. Many species are grown for their edible fruits like passion fruit, granadilla, maypop and sweet calabash, and many simply as beautiful ornamentals.
 

The Zingiberaceae or ginger family contains about 1300 species in 50 genera and is distributed throughout tropical Asia, Africa and the Americas. Its members are strictly fragrant perennial herbs with horizontal rhizomes, often showy flowers and simple distichous leaves with basal sheaths. The flowers are typically strongly zygomorphic in determinate cymes and subtended by spirally arranged bracts. The family takes its epithet from genus Zingiber, the name of which derives from the Greek zingiberis which is what Dioscorides called ginger or some other Arabian spice, and that name is derived in turn from the Sanskrit name of the spice, singabera. It was used in India and China in ancient times. Many species are rich in aromatic, volatile oils and used widely as spices, condiments, dyes and medicines. Some of the spices are ginger, turmeric, cardamom, and numerous others.
 

The Platanaceae or plane-trees make up a very old dicotyledonous family that is considered today as part of the order Proteales and sister family to the Protea family. There is only a single genus in the family, Platanus, which may derive its name from the Greek platys, "broad," referring to the shape of the leaves. This genus contains 6-10 species of trees growing in temperate and subtropical parts of the Northern Hemisphere. They typically have large, flat, simple, alternate and deciduous leaves, flowers in hanging strings of 1-12 dense, globose, male or female flowering heads, and fruits that are indehiscent achenes. The bark is light and often flakes off in large plates. The London plane-tree which is possibly a hybrid of the oriental plane (P. orientalis) and the American plane or sycamore (P. occidentalis) is a very popular urban tree widely planted in cities and tolerant of cold and pollution.



The Oxalidaceae or wood-sorrel family contains only 5 genera but about 800-900 species. It is in the order Oxalidales and is the largest family in that order. Made up of herbaceous plants, shrubs and small trees, most of the species in the family are in the genus Oxalis, which derives its name from the Greek oxys, "sour, sharp," referring to the taste of the leaves. Oxalis corniculata, the creeping wood-sorrel, is a common and widespread lawn weed, as is another, Oxalis pes-caprae, the so-called Bermuda buttercup, which is neither and is in fact native to South Africa. The family also includes the genus Averrhoa or starfruit. The leaves are typically pinnately or palmately compound, often folding up in cold weather or at night, and the flowers are usually bright and showy, radially symmetrical, with 5 petals usually twisted together in bud. The leaves of Oxalis are sometimes used in salads.
 

The Caprifoliaceae or honeysuckle family is because of recent taxonomic work one of the most confusing families I have encountered. The most recent published work (Heywood) gives the number of genera as 12 and the number of species as about 250. It has traditionally been placed in order Dipsacales and is closely related to the Valerianaceae. Some well known genera such as Viburnum and Sambucus have been moved out of the family either to Adoxaceae or to families of their own. Restricted to the northern temperate regions, it is a family of mostly shrubs and viney species with a few herbaceous ones. The leaves are typically opposite and estipulate, and the flowers are tubular and funnel- or bell-shaped, usually with five outwardly spreading lobes, while the fruits are most often berries or drupes. The family's best known members are the honeysuckles. A number of species have edible fruits.
 

The Amaranthaceae or amaranth family is widely distributed across tropical, sub-tropical and temperate regions of the world, but concentrated mainly in Africa, and Central and South America. It is a large family and contains between 70 and 160 genera and between 1000 and 2400 species. The APG II system includes the taxa that were formerly placed in the Chenopodiaceae, which accounts for the disparity in numbers of species and genera. Whether they are in the same family or not, they are certainly closely related. The leaves are simple, estipulate and generally entire. The flowers are usually small and frequently prickly due to the bristly perianth and bracts, they have 4-5 connate petals and are often subtended by bracts or bractlets. Some Amaranth species have grainlike edible seeds that were widely used in Central and South America. Many species are grown today as ornamentals.



The Strelitziaceae or bird-of-paradise family is closely related to and was once considered to be part of the Musaceae or banana family. The Strelitzias are also closely related and superficially similar in habit and appearance to the Heliconias.
All three are in the order Zingiberales.
The giant bird-of-paradise (S. nicolai) in particular looks very much like a large banana tree. There are three genera in this family, Phenakospermum which is endemic to tropical America, Strelitzia, endemic to South Africa, and Ravenala, endemic to Madagascar. These are large herbaceous plants with entire, distichous leaves and distinctive zygomorphic flowers subtended by brightly colored bracts. The fruits are dehiscent capsules. The bird-of-paradise flower (S. reginae) is the best known and is the official flower of Los Angeles. Its name honors Queen Charlotte Sophia of Mecklenburg-Strelitz, wife of King George III.
 

The Alstroemeriaceae or alstroemeria family contains only about three genera and 160-200 species of rhizomatous herbaceous plants and climbers and is restricted to the temperate and tropical regions of Central and South America from Mexico to Chile. The family is monocotyledonous in the order Liliales, and genus Alstroemeria which is commonly called Peruvian lily is a very popular and showy horticultural plant in home and public gardens. The roots of many family members are swollen to store water and nutrients. Leaves are simple, alternate, and entire-margined with parallel veins. The flowers are typically in terminal cymose inflorescences and are subtended by leaflike bracts. They are characterized further by 2 whorls of undifferentiated tepals. The Alstroemeriaceae is considered to be closely related to the Orchidaceae. Some viney species in Bomarea have starchy edible roots.
 

The Hemerocallidaceae or daylily family is a small family of about 40 species in 7-8 genera including the widely cultivated Hemerocallis and the large shrub Phormium or New Zealand flax. Other systems of circumscription have placed the family in the Liliaceae or Xanthorrhoeaceae, and it is considered to be closely related to the Asphodelaceae. The leaves are linear with a sheathed base, some quite long, and distichous, that is with two vertical ranks of leaves on opposite sides of the stem. Phormium and the flax lily Dianella has swordlike leaves. The flowers contain undifferentiated tepals in whorls of three. The fruit is a capsule or berry. Phormium produces fibers used to make cloth. Some family members have medicinal uses, while the daylilies are widely cultivated as ornamental house and garden plants. The family has a wide distribution in tropical and temperate Australasia, the Andes and Madagascar.



The Myoporaceae or myoporum family is a family of herbs and woody plants with 250 species in 7 genera mostly in the southern hemisphere and concentrated particularly in Australia. The largest genus is Eremophila with about 215 species. The family is named after the genus Myoporum, which epithet is derived from the Greek myo, "to close, shut," and poros, "opening, pore," referring to the glands on the leaves. The family is closely related to the Scrophulariaceae. As the Latin name indicates, the leaves and other vegetative parts are characterized by secreting resin glands often appearing as tubercles. The leaves are mostly alternate and estipulate, entire or serrate, and sometimes scaly or woolly. The flowers are solitary or in axillary cymose clusters. The corollas have five lobes either two-
lipped or rotate. Some species produce timber, and some are cultivated for ornamentals.
 

The Nyctaginaceae or four o'clock family is distributed throughout the tropical and warm-temperate regions of the world, with its greatest abundance in the Americas. Best known for the widely planted and brilliantly colorful Bougainvillea, it is in the order Caryophyllales, which includes cacti, carnations, amaranths, ice plants, tamarisks, buckwheats and most carnivorous plants. The family is so-called because of the tendency of many of its members to bloom in the late afternoon and through the night. It contains 300-400 species in about 30 genera, and is characterized by a unique specialized type of fruit called an anthocarp, in which the base of the flower's calyx tightly encloses the seed-bearing achene and is persistent with it. The family contains trees, shrubs, climbers and herbs. Leaves are simple, flowers usually radially symmetrical and sometimes surrounded by colored bracts looking like a calyx.
 

The Globulariaceae or globe-daisy family is recognized by Heywood and under the old Cronquist system of classification, however the APG system places it into the Plantaginaceae, so it is another family that must await more genetic study to determine its correct phylletic position. It appears to be closely related to the Scrophulariaceae, and contains two genera and about 30 species, a number of which are cultivated as rock garden ornamentals. The family's distribution is centered around the Mediterranean and extends as far north as the Baltic and as far south as Somalia. Mostly woody-
based perennial shrubs. The leaves are alternate and usually entire to minutely-toothed. The flowers are either in capitate heads or dense terminal spikes. The tubular corollas are 5-lobed and 2-lipped. Some Globularia species are used as food plants by the larvae of butterflies and moths.



The Araceae or arum family is a group of terrestrial herbaceous plants with flowers in a spadix, which is a spike-like inflorescence with small flowers crowded on a thickened, fleshy axis. According to Heywood's Flowering Plant Families (2007), the family also includes those aquatic species sometimes placed in the Lemnaceae like the duckweeds, and thus includes about 3200 species in 110 genera. This is also where they were placed by APG II. As it is presently constituted, the family has an almost worldwide distribution, excepting only the far north. The aroid species are monocots with a spadix that is enclosed in a leaflike hood. Anthurium and Zantedeschia are the two best known genera, and Amorphophallus titanum has one of the largest inflorescences in the world. Other major members are Philodendron and Monstera. Among the duckweeds, Wolffia has the world's smallest flower.
 

The Saxifragaceae or saxifrage family is restricted almost entirely to the northern hemisphere extending to the high latitudes and elevations, and in the southern hemisphere it is represented along the very western coast of South America. With approximately 650 species in 30-35 genera, the family is comprised of perennial herbs with mostly alternate, simple leaves and flowers that are radially symmetrical with 4-5 free petals. Fruits are usually dry dehiscent capsules. Many species are cultivated as ornamentals for home gardens, while their wild relatives are often inhabitants of rocky crevices and ledges in mountainous terrain. The saxifrage family derives its name from the Latin saxifragus, meaning "stone-breaking or stone-crushing." Familiar Southern California genera are Heuchera, Boykinia, Lithophragma and Jepsonia. Genera Ribes which used to be in the Saxifragaceae is now in a family of its own.
 

The Rhamnaceae or buckthorns are a large family of temperate and tropical shrubs and trees distributed around most of the world. As currently circumscribed, the family contains about 925 species in 50+ genera. The leaves are simple, alternate or opposite, and have stipules. In some species of Paliurus and Colletia, the leaves have been modified into dramatic spines. The flowers are actinomorphic and usually have 4-5 free petals, and although mostly small are sometimes in large brightly colored clusters. A good example is Ceanothus, the so-called wild lilac. Rhamnus species produce various colored dyes, other family members have medicinal uses such as purgatives, stimulants, salves and poultices. The fruit of the jujube tree is a major fruit in China, while other species are cultivated as ornamentals, and there is evidence that many members of the Rhamnaceae contain chemicals related to quinine.



The Aizoaceae which is commonly called either the fig-marigold family or the carpet weed family, is another family that has been circumscribed in various ways. The APG II system puts the Tetragoniaceae, the Sesuviaceae, and the in with the fig-marigolds, but Heywood has now segregated the latter into a family of its own taking with it the bulk of those taxa that were once placed in Aizoaceae and leaving only about 12 genera and 170 species. It is a tropical and subtropical family distributed across most of South America, Africa, Asia Minor and parts of Europe and North America. Mostly annual herbs and woody perennial shrubs with generally small leaves and 1-many-flowered inflorescences. Tetragonia tetragonioides (New Zealand spinach) is grown as a leaf vegetable but is considered as a noxious and invasive agricultural weed in many places.
 

The Iridaceae or iris family contains 70-80 genera and 1800 species. The largest genus in the family and the one that gives it its name is Iris with between 200 and 300 species, one of the most recognizable plants in the world. Irises have a worldwide distribution, including almost all of the Americas, tropical and southern Africa and much of Europe and eastern and northern Asia. These plants are geophytes with underground nutrient storage in corms, bulbs or rhizomes, mostly perennial, leaves usually distichous with a sheathed base. The inflorescenses are typically either 1-many-flowered umbellate cymes or spikes. The usual perianth pattern is to have two whorls of 3 petaloid tepals with the inner whorl sometimes reduced or missing. The family contains many ornamental garden and houseplants that are well known such as Gladiolus, Crocus, Freesia, Watsonia, Dietes, Sisyrinchium, Neomarica and Moraea.
 

The Berberidaceae or barberry family is in the order Ranunculales along with the buttercups and the poppies. It has a distribution that includes all of North and Central America, mostly the west coast of South America, Europe, North Africa and most of Asia, and contains about 15 genera and 650-700 species, the best known of which are Berberis, the barberry, the closely-related hollylike genus Mahonia, and Nandina or heavenly bamoo. The family includes some woody shrubs and rhizomatous or tuberous herbaceous plants usually with alternate and estipulate leaves. The flowers are in cymes, racemes or panicles. The genus Berberis itself contains more than 600 species. Many family members are cultivated for their ornamental value, some have barely edible fruits, others yield dyes and species of Podophyllum have a resin which has purgative or emetic properties and is used in laxatives.



The Loganiaceae, commonly called the logania or strychnine family, contains about 420 species in 15 genera and is in the order Gentianales with the Rubiaceae, the Gentianaceae and the Apocynaceae. The family takes its name from genus Logania, which epithet honors the IrishAmerican colonial statesman, book collector and botanist James Logan. The family is restricted to the world's tropical regions, but is spread everywhere across those areas, and includes annual and perennial herbs, shrubs, climbers and small to large trees. The genus Strychnos yields poisonous alkaloids such as strychnine as well as curare and various fish poisons. Family members also produce some edible fruits and many medicines used to treat fevers, malaria, stomachaches and rheumatism. The leaves are opposite and entire-margined. The corolla typically has a narrow tube with short lobes.
 

The Theaceae or tea family is a small group of 7 genera and 200-400 species in order Ericales. Cronquist listed 40 genera, but the family's circumsciption has been considerably reduced based on DNA studies. Its distribution is centered mainly in tropical South and Central America, tropical Africa and Southeast Asia. Composed of trees and shrubs with simple, evergreen, alternate leaves somewhat leathery and usually with toothed margins, the family's name comes from genus Thea, which epithet derives from either Chinese or Dutch words for tea. The economic importance of the family is tied entirely to the genus Camellia, the leaves of which are harvested on plantations in India, Sri Lanka, China and East Africa. The popular garden camellia which is so well known and so prized for its large flowers and attractive foliage comes in 100+ species and many thousands of cultivated forms
 

The Linaceae or flax family is a small taxa of eight genera and about 180 species almost all contained within genus Linum. Despite being a small family, it is spread over almost all of the Americas, Austrlia, Eurasia and extends down the eastern side of Africa. Composed of primarily herbaceous and occasionally woody herbs and shrubs, family members have some significant economic uses such as flax fibers for fabrics and paper, linseed oil for paints, varnishes and wood preservers, and purgatives and diuretics. Other species are grown as ornamentals. The alternate or opposite leaves are usually sessile and entire-margined, and the flowers are radially symmetrical almost always 5-merous with free, often clawed petals. As currently circumscribed by APG II the Linaceae is placed in order Malpighiales which includes willows, violets, mangroves, passionflowers, St. John's-worts and spurges.



The Alliaceae or onion family are herbaceous perennials either rhizomatous or bulbous with linear or filiform leaves in the order Asparagales. The family includes 600-750 species in 13 genera mostly distributed throughout the Americas and from the Mediterranean to Asia., and currently is thought to exclude those species that are assigned to the Agavaceae, Themidaceae, and Amaryllidaceae. The flowers are terminal on scapes and are usually found in umbels. They are mostly actinomorphic and have 2 whorls of 3 undifferentiated tepals and 6 stamens. The leaves are alternate, distichous or spiral, flat or terete, sheathed, often with an onion smell, and like other monocots have parallel veins. The fruits are non-fleshy, dehiscent capsules. Widely cultivated species in genus Allium include the chives, onions, leeks and garlic. Other familiar family members are Tulbaghia, Muilla and Ipheion.
 

The Escalloniaceae, escallonia or featherwood family, is a small family with about 140 species in 5-7 genera with limited and disjunct distributions in some parts of South America, the southwestern and eastern coasts of Australia, and from the Himalayas to Malaysia. It is unclear at present as to what order this taxa should be assigned to. The family includes trees, shrubs and a few herbs with mostly simple, fleshy or leathery evergreen leaves, regular usually 5-merous flowers in cymose or racemose inflorescences, and capsular or berrylike fruits. The best known genus in the family is Escallonia, the name of which honors a Sr. Escallón who was a Spanish traveller and plant collector in late 18th century South America. It is a popular garden ornamental with shiny leaves and brightly-colored flowers. The same shrub has also been used as a fuel, for charcoal and as a source of dyes.
 

The Agavaceae or agave family is in the midst of circumscriptional revisions and it is difficult to say just what should and should not be included, and where the family should be placed. Heywood gives 9 genera and about 300 species, and according to this circumscription would include the major genus Agave, as well as other desert genera such as Furcraea, Hesperaloe, Beschorneria and Yucca. It appears to be in order Asparagales and contains perennial herbs, trees and shrubs with often succulent leaves arranged in basal rosettes. Some species have a gigantic inflorescence as long as 12m which is usually a terminal or axillary spike, panicle or raceme. The fruits are septicidal or loculicidal capsules with flat black seeds. Agaves have been used to make fibers like sisal and alcoholic drinks like tequila and mescal. Southern Californians are familiar with the yuccas called Our Lord's Candle and Joshua trees.



The Buddlejaceae or buddleja family is a small family of 5 genera and about 120 species. Its main member, Buddleja, named after the Reverend Adam Buddle, an English botanist and rector, was previously placed in either the Loganiaceae or the Scrophulariaceae, and many still consider the Buddlejaceae to be invalid. There is a lot of controversy about taxa that are in this family or were once considered to be related to Buddleja like Polypremum, Nuxia, Peltanthera and Androya. As circumscribed by Heywood, the family is distributed primarily in tropical and subtropical regions in South America, the southern two-thirds of Africa, India and SE Asia. Mostly shrubs and small- to medium-sized trees, the leaves are opposite or in whorls, and the flowers have 4-lobed tubular corollas and 4 stamens. The fruits are dry capsules or fleshy berries. The main economic usage of family members is as ornamentals.
 

The Hydrophyllaceae or waterleaf family is a New World family in order Boraginales related to the Boraginaceae and similar to them in having inflorescences which are often dense helicoid cymes. Study is still going on with these two families and they may end up merged. The family consists of 15 genera and about 300 species and contains annual and perennial herbs and shrubs and even some small trees, including many very familiar to southern Californians like Phacelia, Pholistoma, Nama, Eucrypta, Eriodictyon, Turricula and Emmenanthe. The leaves are usually alternate. The flowers are 5-
merous and essentially actinomorphic, either opening as the inflorescence coil unwinds or solitary in the leaf axils. The fruits are dehiscent capsules. Little economic importance is attached to members of this family, some are cultivated as ornamentals, and a few others have some local uses.
 

The Salicaceae or willow family has some 385 species in only two genera but is distributed virtually worldwide. The two genera are Salix with 350 species and Populus with about 35 species. One of the things that characterizes this family are the catkins of flowers which lack a typical perianth. As with so many other cases, this is the circumscription according to Heywood's Flowering Plant Families of the World (2007). The APG system has a very different analysis with 55 genera and 1000+ species, many of which are considered more recently to be properly placed in Flacourtiaceae. Many family members are planted as ornamentals and others have been utilized for baskets and cricket bats. Salix bark originally was used to produce aspirin. The arctic willow inhabits the North American tundra where the temperatures range from -70° to 20°F. It grows to only 8" tall. The weeping willow is another popular tree.



The Pittosporaceae or pittosporum family contains about 200 species in 9-10 genera restricted to the Old World and mostly to the tropics. All the genera but Pittosporum itself are endemic to Australia. Pittosporum derives it name from the Greek pitta, "pitch or resin," and sporos, "a seed," referring to the seeds which are covered with a resinous, sticky pulp. The family consists mainly of small trees and shrubs which are often aromatic. The leathery evergreen leaves are typically alternate and entire. The five-petalled flowers are usually connate at the base in various types of inflorescences including umbels, corymbs and panicles, and sometimes solitary. Fruits are berries or loculicidal capsules. The main economic significance of Pittosporums is as ornamentals because of their handsome foliage and beautiful flowers. At least one species called apple berry produces edible fruits.
 

The Brassicaceae or mustard family is a huge family of major economic importance that has an almost worldwide distribution, but concentrated particularly around the Mediterranean and in south-
western and central Asia. According to Heywood, it contains some 340 genera and well over 3000 species, and is in the order Capparales with Capparaceae and Resedaceae. The family previously went by the name Cruciferae, which meant "cross-bearing" and referred to the four petals in a cross-like arrangement. There are many well-known species and cultivars in the family including cabbage, mustards, cauliflower, broccoli, turnips, bok choy, kale, radishes, stock and a host of others, some of which been cultivated for as long as 8,000 years. Rapeseed oil is now second to soybean oil, supplying 13% of the world's total, and many family members are grown as forage crops and ornamentals.
 

The Zamiaceae or zamia family is not a flowering plant family but rather one of cycads, which are primitive, superficially palm- or fern-like, evergreen, dioecious gymnosperms. The family contains eight genera and about 150 species, and they are distributed in the tropical and warm temperate regions of Africa, Australia and North and South America. The leaves are single-pinnate and spirally-
arranged. The reproductive structure is a determinate cone formed by small spore-bearing leaves called sporophylls. The female sporophylls have a thickened blade with two or three sessile ovules on the inner surface facing the axis. Genus Zamia has about 50 species and is native to the Americas. Dioon grows from Mexico to Nicaragua with 11 species. Encephalartos is native to Africa with about 65 species. Members of the Zamiaceae are poisonous, producing poisonous glycosides known as cycasins.



The Hyacinthaceae or hyacinth family is very much in question as to its validity as an independent family. Cronquist put it in the Liliaceae, and APG puts it in Asparagaceae, and it is still under study. As circumscribed by Heywood, the family contains about 900 species of usually bulbous herbs in 70 genera distributed widely but concentrated mainly in areas with Mediterranean climate. The myth is that Hyacinth was accidentally killed when the god Apollo hit him with a discus, and then made a flower out of his blood. The leaves are basal, filiform to elliptic, and flat to terete. The flowers are in a 1-many-flowered racemose or spicate inflorescence. The fruit is a loculicidal capsule. Many species are widely cultivated as home and garden plants, and others for cut flowers. A couple of species contain cardiac glycosids used to treat congestive heart failure and cardiac arrhythmia.
 

The Cupressaceae or cypress family contains 25-30 genera and about 140 species of coniferous trees and shrubs, and is in fact the most widely distributed of all conifer families, extending from arctic Norway to southernmost Chile, and growing to 17,000' in Tibet, the highest altitude reached by any woody plant. The family currently includes species previously treated as Taxodiaceae. The leaves are scalelike, and arranged either in decussate pairs or decussate whorls. Immature leaves and mature leaves of some species are needle-like. The seed cones are woody, leathery, or berry-like and fleshy, with 1-several ovules per scale. Many cypress family members provide excellent timber, junipers are good groundcovers and have been widely cultivated, dawn redwoods have been extensively planted as ornamentals, and juniper oils have been used as perfumes and medicines.
 

The Piperaceae or pepper family is a family circumscribed with only 5 genera but containing about 3000 species, which is an extraordinary number of species for such a small number of genera. It is in the order Piperales along with the families Saururaceae and Aristolochiaceae, and is distributed mainly in tropical and subtropical regions. The Piperaceae includes small trees and shrubs, climbers and herbs, some of which are epiphytic. The leaves are entire and arranged in a variety of configurations, and the spicate, terminal or axillary inflorescences are either erect, arched or pendulous. The fruits are drupes or berries, and when those of Piper are dried they are referred to as peppercorns. The best known species of the family is Piper nigrum or black pepper. The large genus Peperomia has well over a thousand identified species and has been widely cultivated as an ornamental.



The Cycadaceae, commonly called the cycad family, holds only a single genus, Cycas, with about 95 recorded species, and although the Zamiaceae is often referred to as the sago palm family, that name should perhaps not be used since sago palms are in the Cycadaceae. The cycads are palmlike, dioecious, seed-bearing trees or shrubs which have thick, pithy trunks with spirally-arranged and pinnately-compound leaves clustered at the top of the stem. The reproductive organs of Cycas are groupings of leaflike structures each with seeds on the lower margins on the female plants and pollen cones on male plants. Individual plants generally grow some 10 years before any reproductive activity takes place. In some species, the main trunk is actually underground and the leaf crown seems to rise directly from the ground. An ancient taxa, cycad fossils have been found from the Mesozoic era.
 

The Violaceae or violet family has about 22 species and almost 900 species of trees, shrubs, and both lowland and alpine herbs with an almost worldwide distribution but concentrated pantropically. The leaves are typically alternate and simple with entire to serrate margins, and the flowers divided half and half between radially symmetrical and zygomorphic with 5 sepals and 5 unequal, linear to orbicular petals, the anterior of which is larger and often spurred. The fruits are frequently 3-valved capsules, but sometimes fleshy berries, nuts, follicles or other. Newer classification systems place the Violaceae in the order Malpighiales which is a large order including pinks, willows, flaxs and spurges. The family is named after the genus Viola which has 400-500 species of mostly northern temperate plants. Some uses that family members have are for timber, bird lime, traditional medicines, and ornamentals.
 

The Polemoniaceae or phlox family contains between 350 and 380 species in about 20 genera, and is currently placed in order Ericales close to the families Styracaceae, Fouqieriaceae and Primulaceae. The family is comprised of mostly herbaceous genera centered in western North America and woody plants and climbers distributed mainly from Mexico to the Andes. Some species reach quite high altitudes. There is little about the leaves that the family shares in common, and the flowers are typically 5-merous but sometimes with parts in 4's or 6's, in inflorescences of cymes, corymbs or heads or solitary, and usually actinomorphic. The main importance of members of this family is as ornamentals in temperate gardens. Phlox was a Greek name for flame or plants with flame-colored flowers. Polemonium was a name possibly applied to a medicinal plant associated with Polemon of Cappadocia.



The Melianthaceae or honeyflower family contains 5 genera and about 18 rather diverse species. Limited to Africa with the exception of the monotypic Chilean genera Francoa and Tetilla, the family consists of small trees and shrubs with alternate, pinnately compound leaves and flowers in terminal racemes. The genus Greyia has been considered in its own family, but now is in this one. The family name is derived from the Greek meli, "honey," and anthos, "flower," alluding to the nectar-rich blossoms. Some species have had medicinal uses such as treating snake bites and other wounds, the wood of other members has been used as timber and for carving utensils and ornaments, and burned as incense. The flowers are mostly radially symmetric, 4-5-merous with 4 or 5 free petals. The fruit is a papery or woody dehiscent capsule, either loculicidal or opening only at the tip.
 

The Begoniaceae or begonia family has about 1400 species in only two genera! Even more amazing than that, all but one of the species are in genus Begonia, the other in genus Hillebrandia endemic to the Hawaiian Islands. The family is mainly confined to the tropics but does reach as far north as the Ryukyu Islands and as far south as South Africa. Primarily semi-succulent herbs and small shrubs, the leaves are alternate and quite stipulate with asymmetrical blades and the flowers are in a cymose inflorescence with undifferentiated sepals and petals but often opposite and unequal pairs. The fruits are capsules or berries with numerous minute seeds. Begonias have been extensively cultivated as house and garden plants with some 10,000 recorded cultivars. The name Begonia honors the 17th century French patron of botany Michel Bégon, governor of French Canada and San Domingo.
 

The Buxaceae or box family is a small one with about 120 species in 4-5 genera and is widely scattered in tropical, sub-tropical and temperate areas but centered primarily in eastern Asia and in parts of Central America and the Caribbean. It appears to be in the order Buxales, a small order containing only one other family. Comprised mainly of evergreen shrubs and smallish trees, the leaves are simple and estipulate, and often leathery. The flowers are radially symmetrical in axillary or terminal spikes, racemes or clusters. The fruits are either loculicidal capsules or drupes with black, shiny seeds. Box shrubs are widely grown mostly as ornamentals for landscape use as hedging and other family members as a ground cover. The hard dense wood of some species has been utilized for carving and inlaying furniture. Buxus was the classical Latin name used for the box shrub by Pliny.



The Tropaeolaceae or nasturtium family contains a single genus, Tropaeolum, and about 90 species. They should not be confused with genus Nasturtium in the Brassicaceae. Family members are twisting, somewhat fleshy herbs that con-
tain mustard oils in their sap similar to those in watercress (N. officinale). The leaves are alternate and peltate, that is with the leaf stems attached to the undersurface of the leaf, and the flowers are showy, zygomorphic and spurred, and arise singly from the leaf axils. There are five petals and five sepals, one of which is modified to form the spur. The fruit is a 3-seeded schizocarp. At one time or another the family was placed in orders Geraniales and Tropaeolales, but is now considered part of the Brassicales. The family is best known for its cultivated ornamental, the garden nasturtium. Another member, the mashua, is an important root crop in the Andes region.
 

The Malpighiaceae or malpighia family is a medium-sized family containing about 75 genera and 1300 species of trees and self-supporting or climbing shrubs often characterized by two-branched unicellar hairs. The simple, usually opposite leaves often have pairs of glands on the petiole or at the base of the blade. The flowers are mostly radially symmetric with five sepals and five typically clawed petals. There are family members in the tropical and subtropical regions, mostly savannah and forests, of both the Old and New Worlds, but the greatest diversity and main concentration resides in the tropical Americas, particularly Brazil. The family has been moved from the Polygalales to the diverse Malpighiales which includes violets, willows, passion-fruits, mangrove, poinsettia and flax. Many species in the family are cultivated as ornamentals, and others produce vitamin C-rich fruits and hallucinogenic compounds.
 

The Casuarinaceae or casuarina family contains about 100 species in just 4 genera. The family is in the order Fagales, which also includes birches, beeches, oaks and walnuts, and is native to mostly tropical areas of Southeast Asia, Australia and the Pacific islands. Although the family contains some shrubs, it is mainly comprised of fairly tall evergreen trees with a somewhat 'weeping' appearance caused by equisetoid twigs that typically are grooved, circular in outline and have short internodes. The leaves are not evident as such, being whorls of toothed sheaths surrounding stem joints. The flowers are also reduced, male flowers in terminal spikes toward the top of the tree and female flowers in dense heads on side branches lower down. Timber from many species is hard and useful for the manufacture of furniture. Common names for casuarina are she-oak, beefwood, ironwood and bull-oak.



The Ulmaceae or elm family contains around 130 species in 15 genera, and is in the order Rosales, an order which also includes roses, mulberries, buckthorns and nettles. The family is widespread in tropical and temperate regions, and is made up mostly of fairly tall trees with some shrubs and lianas. Leaves are typically alternate, occasionally opposite, simple and stipulate, margins either entire or crenate/dentate. The flowers are regular, either solitary of in terminal cymes or racemes, and are small and grrenish with 4-5 tepals. Fruits are indehiscent, either samaras or fleshy drupes. Members of the family provided good quality timber and wood for furniture but have been decimated by Dutch elm disease. Other members have bark that has been used for fibers, and hackberry (Celtis) has edible fruits, although some circumscriptions place this genus elsewhere. Slippery elm has medicinal qualities.
 

The Juglandaceae or walnut family is a family of 8 genera and about 60 species of wind-pollinated trees in the order Fagales. The family name came from the genus Juglans which epithet is said to derive originally from the Latin name of Jovis glans or Jupiter's nut, a nut fit for a god. Concentrated mainly in temperate and sub-tropical areas of the Northern Hemisphere, the family also extends into the tropics of Asia and as far south in South America as Argentina, but is absent from Africa and Australia. Leaves are usually deciduous, mostly alternate, resinous and glandular, and compound, and the leaf blades are pinnately veined. The male flowers are most often in long, drooping catkinlike inflorescences and the female flowers in erect or pendulous spikes. The fruits are 1-seeded and indehiscent drupes, nuts or samaras. Producing valuable timber, they are best known for edible walnuts, pecans and hickories.
 

The Betulaceae or birch family contains six genera and 130 species of trees and shrubs including in addition to the birches, hazels, alders and hornbeams. Betula is the old Latin name for this genus while the name birch is derived from an old Germanic root, birka, in turn from a root meaning 'white, bright; to shine.' The family is primarily a boreal and cool temperate one with extensions in the higher elevations of Central and South America. The leaves are deciduous, alternate, simple, stipulate and usually with dentate margins. The male flowers are in pendulous catkins and the female flowers are either in erect or pendulous catkins or in 2-3-flowered clusters. The fruit is an indehiscent one-seeded often winged nut or samara. Species of Corylus produce hazelnuts and filberts. Hornbeams have especially hard wood historically used for cartwheels, water wheels, tool handles and chopping boards.



The Balsaminaceae or balsam family is interesting because although it only includes 2 genera, within those 2 genera there are approximately 900-1000 species, almost all of which are in the genus Impatiens. Composed of annual and perennial herbs, the family is one of temperate and tropical regions, being well represented in China, Southeast Asia, India and Sri Lanka, Madagascar and tropical Africa. Only a few native species inhabit the Americas. The leaves are in various configurations and are typically simple, often with translucent stems, and contain a watery juice. The flowers are either solitary or in axillary cymose inflorescences, and although irregular and zygomorphic are basically 5-merous with 4 petals being connate and 1 distinct. The fruit is an explosive capsule which gives rise to another of the family's common names, touch-me-not. Impatiens are used as potted plants or ornamentals.
 


The Flacourtiaceae or flacourtia family is a large one with about 900 species in 80 genera. The family name honors the Director of the French East India Company and Governor of Madagascar Étienne de Flacourt. Widespread in the tropics and subtropics, family members are absent from Europe and the Mediterranean basin. Comprised of trees and shrubs, the family is characterized by alternate, evergreen, non-aromatic, stipulate and entire- to dentate-margined leaves, and flowers that are either solitary or in a variety of different inflorescences of which the most typical is a terminal or axillary cyme or raceme. Individual flowers often have many stamens. The fruits include fleshy or non-fleshy berries, capsules, and drupes. Some taxonomists have referred species in this family to the Salicaceae and Achariaceae. Usages of family members have been as timber, oils used for skin diseases, and ornamentals.
 

The Primulaceae or primrose family contains 21 genera with about 900 species, and is in the order Ericales, which includes such diverse members as kiwifruit, phlox, Brazil nuts, persimmons, camellias, tea, ebony, rhododendrons, blueberries and heathers. The primrose family extends over the entire subarctic northern hemisphere, and is also fairly well represented in South America and Africa, but almost absent from Australia. The two largest genera in the family are Primula and Androsace. Family members are annual and perennial herbs with simple, usually entire-margined leaves. Flowers are often scapose, either terminal or axillary, and solitary or in heads, umbels, or panicles. The fruits are non-fleshy, usually dehiscent capsules. The family has little economic significance except for their horticultural use which is considerable. Primroses are so-called because they are the first spring "roses" to bloom.


The Balsaminaceae or balsam family is found throughout temperate and tropical regions, mostly in Africa and Asia, but also in Europe and North America. It is a family in the order Ericales, and consists of the genus Impatiens with more than a thousand species and the monotypic genus Hydrocera with only a single species. The family was previously included in the Geraniaceae. Certain species of Impatiens in geographically-diverse regions of the world have been used topically as remedies for eczema and other skin conditions including dermatitis from poison ivy. Hybrids or cultivars of certain Impatiens species are commonly grown as house and greenhouse plants. Other economic uses have been as cosmetic dyes and foods. The Balsaminaceae are distinctive in being mostly herbs with translucent aerial stems, simple leaves, zygomorphic flowers, and a fruit that is a drupe or a touch-sensitive, explosively dehiscent capsule.
 
The Primulaceae or primrose family is a family of mostly herbaceous flowering plants including some favorite garden plants and wildflowers. Most are perennial though some species, such as scarlet pimpernel, are annuals. The taxonomic history of Primulaceae has been long and complex. Previously one of three families in the order Primulales, it has now been placed in the order Ericales. The family shares the characteristic of haplostemonous flowers with stamens opposite the petals. Mostly herbaceous, they have no woody stems, but can form cushions or mats a few inches tall. Leaves are simple and exstipulate, and leaf arrangement is typically alternate but occasionally opposite or whorled. Flowers are bisexual with radial symmetry. The calyx is persistent after flowering. The Primulaceae family takes its name from the type genus Primula which Linnaeus used to reflect its place among the first flowers of spring.
 
The Celastraceae or staff-vine, bittersweet or spindle tree family is a family of mostly tropical herbs, vines, shrubs and small trees, belonging to the order Celastrales. It includes almost a hundred genera and about 1,350 species, growing in a wide variety of habitats including woodland, rain forest, grassland, coastal dunes and very dry areas. One of its genera, Parnassia, may be found in alpine and arctic climates, and 19 genera are native to Madagascar. The fruits of the family are often brightly colored drupes or capsules, and the leaves frequently leathery, sometimes toothed around the margins. The flowers are small, with four to five sepals and petals, alternating between the petals, and stamens rising from a typically consipcuous nectar disk. Members of the family are useful for medicinal extracts, insecticides, seed oils, wood for timber, stems for basket weaving, stimulants, poison for arrows, and for infusions to be drunk as a tea.


The Hydrangeaceae is a fairly large-sized family of woody ornamental trees, shrubs, vines, and herbs, native primarily to tropical, subtropical, and north temperate regions in Asia and North America, and locally in southeastern Europe. It is included in the order Cornales, with 19 genera and about 260 species, characterized by leaves in opposite pairs (rarely whorled or alternate), and regular, bisexual flowers with 4 (rarely 5–12) petals. The fruits are capsules or berries containing several seeds with fleshy endosperms and sometimes winged. There are several genera in this family residing in California such as Philadelphus, Carpenteria, Fendlerella and Jamesia. Many Hydrangea species are dioecious, with separate male and female plants and many of the genera are ornamentals. The name of this plant family is derived from the Latin, hydor, meaning water, and aggeion, meaning vessel or cup, referring to the shape of the fruit.
 
 
 



References:

Heywood, V.H. et al. (2007) Flowering Plant Families of the World
Koekemoer, M., Steyn, H.M., and Bester, S.P. (2015) Guide to the Plant Families of Southern Africa
Smith, James Payne, Jr. (1977) Vascular Plant Families
Walters, Dirk R. and David J. Keil (1996) Vascular Plant Taxonomy

Internet references:

Angiosperm Phylogeny Group Angiosperm Phylogeny Website
International Plant Names Index
Watson, L. and M.J. Dallwitz The Families of Flowering Plants



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