Triangle-leaf Bursage Triangle-leaf
bursage is a native plant of the Sonoran Desert and
can be found throughout southwestern Arizona, USA,
south into Sonora and Baja California, Mexico.
Triangle-leaf
bursage can be found growing in upper and lower
bajadas, lowland creosote growths and desert
grasslands. It grows at altitudes of 1,000 to 3,000
feet on open flat, spaces, and steep, gravely
hillsides. Triangle-leaf bursage prefers to grow in
coarse soils with a high pH where rain Triangle-leaf bursage is a small, round shrub about 1 1/2 feet tall and 2 feet wide. It has many slender and brittle branches that grow from the base to create a dome-like crown. The crown contains many old, dead growth. Young branches and leaves are hairy and resinous, but become smooth with age. The triangle shaped leaves are about 1 inch long and 1/2 inch wide. The margins are serrated but can sometimes be smooth. They have a gray-green color on top and are white and fuzzy underneath. Triangle-leaf bursage is drought deciduous and will lose its leaves during the dry seasons. Triangle-leaf
bursage has small, 1/4 inch wide yellow-green
flowers without petals. They grow in pairs from the
end of growth spikes and flower from February to
July. Bursage gets its name from its burr-like
seeds. The round seeds are covered with hook-tipped
spines that attach themselves to the fur of passing
animals. The plants produce many seeds after both
summer and winter rains. For a
desert plant it has a short life-span, only 50
years. Its most significant function is as a "nurse
plant" for other species. Because it prefers to
grow in open, sunny areas, it is one of the first
plants to populate an empty space too hot for other
seedlings. Once it is established, it provides a
microhabitat for the seedlings of other species and
protects them from herbivores with its tangle of
branches. In time the area becomes populated with
many different species of desert plants. The triangle-leaf bursage is a member of the Sunflower family and a cousin of common ragweed. 2002
bibliography: "Ambrosia deltoidea", http://www.fs.fed.us/database/feis/plants/shrub/ambdel/ "Master Plant Description", http://www.mswn.com/MSWNmasterplantlist%20A.htm#Ambrosia%20 deltoidea "Triangle Leaf Bursage Description", http://www.scenicdrive.org/pdbur.htm
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