Common Cocklebur
Xanthium strumarium, Sunflower or Sunflower Family (Compositae) or (Asteracae), Common Cocklebur. Also called: Clotbur, Rough Cocklebur, Large Cocklebur, Common Cocklebur, Xanthium americanum, Xanthium chinense, Xanthium macrocarpum.
Common cocklebur is a coarse, erect, summer annual that produces a conspicuous prickly "cocklebur" and ranges from about 1/2 to 6 1/2 feet in height. It is considered a weed and it grows just about everywhere in the USA.
Height: Up To About 1/2 to 6 1/2 Feet Tall.
Flowers: Greenish Yellow grapelike clusters of male flowers on a stalk at the leaf axils. Female flowers are smaller at first, just below male, becoming the "bur" fruits.
Blooming Time: July to September.
Fruit: The fruit is An elliptic shaped two - chambered bur, 1/2 to 1 1/2 inches long and covered with hooked prickles. Each bur contains two seeds, one which grows during the first year and one that grows a year later.
Leaves: The first true leaves are opposite, all subsequent leaves are alternate. The alternate triangular to ovate leaves have stiff hairs, and are approximately 2 to 6 inches long. They are irregularly lobed with leaf margins that have relatively inconspicuous teeth.
Found: Throughout Arizona.
Elevation: 0 to 7,000 feet.
Habitat: Commonly found in distrurbed ground, cropland, stream banks, edge riparian.
Miscellaneous: Photos Taken September 28, 2008. At Flora Mae Park Riparian Area, Yarnell, Arizona.
