Annual bur-sage, or sand-bur as it is also called, is an erect, branched annual that grows to about 30" tall from a slender taproot with sparingly hispid stems, winged petioles and bipinnatifid leaves ± ovate in outline.  The numerous staminate flowers heads are about 1/8" in diameter and hang down from higher up on the stem, and the pistillate heads are 1-flowered in the leaf axils.  The fruit is an ovoid bur with 9-18 straight flattened spines that are pale golden in color.  Annual bur-sage is a common weedy plant that prefers sandy soils, creek bottoms, roadsides in many communities from cismontane s. California to desert edge and extending to Washington and Texas. It blooms from August to November.

Click here for Latin name derivations: 1) Ambrosia 2) acanthicarpa.
Pronunciation: am-BRO-zee-a ak-an-thi-KAR-pa.
Click here for Botanical Term Meanings.