Giant coreopsis is an erect, shrubby, glabrous
few-branched perennial with a stout, fleshy trunk growing to some 8'
tall. The main trunk grows up to 5" thick and often resembles
a small tree. The leaves on a young plant are an array of pinnately-divided
filiform segments, and on a mature plant are 3-4-pinnatifid into fleshy,
linear segments clustered at the ends of branches. The leaves
are deciduous in the dry season when the plant is decidedly unattractive,
but during its blooming season, March to May, it bursts forth with a
mass of showy, bright yellow flowers and green leaves. The large
radiate flowering heads are in cymes on long scapiform peduncles and
are up to 3" in diameter. Each is leafy-bracted and has a
bell-shaped involucre and two series of phyllaries, the outer of which
are lance-oblong and the inner oblong-ovate. There are 10-16 fertile
yellow ray flowers and numerous yellow 4-toothed disk flowers. The
fruit is a glabrous, brown, obovate to oblong achene with no pappus.
Giant coreopsis may be found on rocky cliffs and exposed slopes
and dunes along the immediate coast from Los Angeles Co. to San Luis
Obispo Co. and on the Channel Islands. A related species, C.
maritima or sea dahlia, is smaller and grows further south. These
pictures were taken near Point Dume.
Click here for Latin name derivations: 1) Leptosyne
Pronunciation: lep-toe-SY-nee ji-GAN-tee-a.
Formerly Coreopsis gigantea.
Click here for Botanical