Weeds

Cocklebur, Spiny

Cocklebur, Spiny
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Spiny Cocklebur (Xanthium spinosum L.)Spiny cocklebur is an erect, much branched annual that grows up to three feet high. It reproduces by seed. About one inch long spines are found in leaf axils and at stem nodes. The leaves are shiny dark green and hairy on the upper surface and downy beneath. The leaves are mostly three-lobed with the center lobe much longer than the other two, and up to three inches long. The flowers are small, inconspicuous, and creamy green. The male flowers are found at the top of the stems and the female flowers are formed lower on the stems. The fruit is more or less an egg-shaped burr, up to one-half inch long, armed with numerous hooked spines, some with one or two straight terminal spines. There are two seeds per burr, flattened, three-eighths inch long and brown in color. The seeds and cotyledonary seedlings are poisonous. Ingestion of seeds equal to 0.3 percent of the animals weight, or ingestion of seedlings equal to 1.5 percent of the animal’s weight are toxic. Poisoning has occurred in all classes of domestic livestock, and is always associated with cotyledonary seedling ingestion. The symptoms are anorexia, depression, nausea, and prostration. Death may occur in a few hours to three days after the symptoms are first noted.