Spikeweed (Hemizonia pungens)
EDRR Species?:
No
Other common names
Common tarweed, Maritime spikeweed
Description
Annual that blooms July to September. This plant grows 1 1/2 to 3 feet tall and has basal leaves that are pale, straw-colored, stiff, several inches long, with narrow lobes. Stem leaves are 1/2 inch long or less and sharp-pointed, bearing dwarf stems in their axils. Flower heads are yellow, 1/3 inch broad, and borne at the tips of short leafy branches.
Impacts
Occurs on roadsides, waste areas and in low alkaline sites of grain fields and rangelands. Spikeweed is a tough, spiny plant avoided by livestock. It is a heavy seed producer and forms dense stands in areas favorable to its growth.