Ambrosia eriocentra
Encyclopedia
Ambrosia eriocentra is a species of ragweed
known by the common names woolly bursage and woollyfruit burr ragweed.
It is native to the southwestern United States where it grows in the deserts and surrounding ridges up to about 1700 meters in elevation. This is a rounded shrub
reaching over 1.5 meters in maximum 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 fruit is a green burr
with long, silky white hairs and several hair-tufted sharp spines. The burr is around a centimeter long.
Ragweed
Ragweeds are flowering plants in the genus Ambrosia in the sunflower family Asteraceae. Common names include bitterweeds and bloodweeds....
known by the common names woolly bursage and woollyfruit burr ragweed.
It is native to the southwestern United States where it grows in the deserts and surrounding ridges up to about 1700 meters in elevation. This is a rounded shrub
Shrub
A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...
reaching over 1.5 meters in maximum 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
Petiole (botany)
In botany, the petiole is the stalk attaching the leaf blade to the stem. The petiole usually has the same internal structure as the stem. Outgrowths appearing on each side of the petiole are called stipules. Leaves lacking a petiole are called sessile, or clasping when they partly surround the...
. The leaves have rolled lobed or toothed edges. As in other ragweeds, the inflorescence
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
has a few staminate
Stamen
The stamen is the pollen producing reproductive organ of a flower...
(male) flower heads
Head (botany)
The capitulum is considered the most derived form of inflorescence. Flower heads found outside Asteraceae show lesser degrees of specialization....
next to several single-flowered pistillate
Gynoecium
Gynoecium is most commonly used as a collective term for all carpels in a flower. A carpel is the ovule and seed producing reproductive organ in flowering plants. Carpels are derived from ovule-bearing leaves which evolved to form a closed structure containing the ovules...
heads. The fruit is a green burr
Burr (fruit)
A bur is a seed or dry fruit in which the seeds bear hooks or teeth which attach themselves to fur or clothing of passing animals or people. The hooks or teeth can be irritants and very hard to get off of clothing, such as wool or cotton...
with long, silky white hairs and several hair-tufted sharp spines. The burr is around a centimeter long.