Xanthium strumarium L.
Description:
Annual plant whose seedling and seeds are poisonous.
The dark green secondary leaves are alternate, oval to heart shaped, mostly complete, have a toothed margin and are rough top and bottom. The leaf may be 5-6 inches across and the petiole is generally longer than the leaf.
The purple spotted stem is erect and very branched, rough, ridged, and up to 4 ft tall.
Flowers are small green and inconspicuous growing in the axils of the leaves and at the ends of the stems.
Flowers develop into inch long, oval seed cases covered with hooked spines. Velcro was developed after the hooks on the seed casing. Each bur contains 2 long thin seeds with pointed ends; ridged on one side smoother on the other.
The toxins are glycoside, carboxyatractyloside, hydroquinone and sesquiterpene lactones. The seeds and seedlings contain the highest quantity of toxins. All animals may be affected, cattle, swine, sheep and poultry are more at risk than horses or pets, the burs irritate and catch in fur and clothing.
Symptoms:
Gastrointestinal irritation, weakness, breathing difficulty, hypoglycemia, cardiac abnormalities, death. Liver damage may result from toxins and death is likely if 0.75% of body weight is ingested.