Cressleaf Groundsel

Latin Name: Xanthium strumarium

Identifying Characteristics:  Starts growing as a rosette, starts growing laterally in spring producing yellow flowers, hollow, hairless stems

Plant Longevity: Winter annual

Where Commonly Found: No till systems or pastures; moist soils

Time of most concern: Spring

Compound that causes concern: Pyrrolizidine alkaloids that cause chronic liver damage

Part of plant most toxic: Leaves, flowers and seeds

Livestock species affected: Cattle - 30-40 times more susceptible than sheep or goats. Calves and younger cattle are more susceptible than older cattle

Pasture, Stored Feed or Both: Pasture, hay

Symptoms: Loss of appetite, depression, aimless walking, diarrhea, anorexia

Amount needed to be consumed for symptoms/death if known - English units: In cattle, 4-8% of their body weight of green plant (over the course of a few days.) In cattle, 2-2.5% of their body weight of dry matter (per day)

More information

Pictures of stages of growth: