1. Buffalo bur (Solanum rostratum) Prickly annual of the potato family typically growing up to 2’ tall. This plant can poison horses, sheep, goats and cattle, however sheep and goats resist more than cattle.

2. Whitebrush, Beebrush (Aloysia lycioides) An aromatic shrub of the vervain family that grows from 3-10’ tall. Toxic agent unknown. Horses, mules and burros are suspected to be poisoned by this plant. Actual toxin involved has never been identified but does dissolve in water.

3. Hairy Caltrop (Kallstroemia hirsutissima) Much-branched annual with long, prostrate limbs from a central root. Toxic agent is unknown, toxic to cattle, sheep, goats and rabbits.

4. African Rue (Peganum harmala) Member of the caltrop family, bright green, succulent, perennial herb growing from a woody base. Toxic agent contains at least four poisonous alkaloids, is toxic to cattle, sheep and probably horses.

5. Goathead, Puncturevine (Tribulus terrestris) Annual weed in the caltrop family. The plant causes hepatogenic photosensitization in sheep, and cattle are suspected. All parts of the plant are toxic at all growth stages, but wilted plants are the most hazardous.

6. Whole plant