Ambrosia eriocentra is a North American species of ragweed known by the common names woolly bursage and woollyfruit burr ragweed.[1]
The plant is native to the Mojave Desert in the southwestern United States, within southern California, southern Nevada, northwestern Arizona, and southwestern Utah.[1]
It grows in the Mojave's plains and mountain ridges up to 1700m (5,600feet) in elevation.[2]
Ambrosia eriocentra is a rounded shrub reaching over 1.5m (04.9feet) in height. The stems are brownish gray in color, with young twigs coated in light woolly fibers and older branches bare. Leaves are lance-shaped and up to 9 centimeters long, not counting the winged petioles. The leaves have rolled lobed or toothed edges.
As in other ragweeds, the inflorescence has a few staminate (male) flower heads next to several single-flowered pistillate heads. The bloom period is April to June.
The fruit is a green burr with long, silky white hairs and several hair-tufted sharp spines. The burr is around a centimeter long.[3] [4]