Ambrosia eriocentra, Woolly Bursage
Scientific Name: Ambrosia eriocentra
Common Name: Hollyleaf Bursage
Also Called: Woolly Bursage and Woolly Fruit Bur Ragweed
Family: Asteraceae, Sunflower Family
Synonyms: (Franseria eriocentra)
Size: Up to 4 feet or more.
Growth Form: Shrub, subshrub, erect woody spreading branches, rigid; stems grayish-brown, stems woolly becoming smooth with age.
Leaves: Grayish-green to white, lanceolate, margins irregularly lobed (pinnatifid-like) and toothed, short leaf stalk or petiole (sub-sessile).
Flower Color: Greenish, inconspicuous, both male (staminate) and single flowered female flowers (pistillate) (monecious) on flowering stalk (inflorescence), fruit a fusiform hairy bur about 1/3 inch long, seed is an achene.
Flowering Season: April to May.
Elevation: 1,500 to 5,000 feet.
Habitat Preferences: Desert and pinyon-juniper habitats, sandy soils, gravelly washes and benches along dry desert washes.
Recorded Range: In the United States in AZ, CA, NV and UT. In Arizona Hollyleaf Bursage is found in the central and northwestern parts of the state.
North America & US County Distribution Map for Ambrosia eriocentra.
U.S. Weed Information: No data available.
Invasive/Noxious Weed Information: No data available.
Wetland Indicator: No data available.
Threatened/Endangered Information: No data available.
Genus Information: 25 species in Ambrosia throughout the United States and Canada. 15 species in Arizona which now includes members of the former genus Hymenoclea. Plants in the genus Ambrosia are referred to by the common name Ragweed. This species was formerly included in the genus Franseria.
Comments: Hollyleaf Bursage is a Mojave Desert species, common where found in Arizona. It has a similar distribution to White Bursage Ambrosia dumosa a close relative that is also a Mojave Desert species.
Also see in Southwest Desert Flora; Canyon Ragweed, Ambrosia ambrosioides, Triangle-leaf Bursage, Ambrosia deltoidea, White Bursage Ambrosia dumosa, Burrobush, Ambrosia monogyra and Cheesebush, Ambrosia salsola.
It is one of several Ragweed species whose pollen causes severe hay fever and allergies in some people. This species thrives in alkaline soils and has the ability to withstand very high surface temperatures for extended periods and often looks lifeless.