It’s summer in Texas—high temperatures, little rainfall and pasture grasses stressed. That’s a situation that could lead to serious trouble for cattlemen as livestock may find green, toxic plants tempting.

A Texas A&M Veterinary Medical Diagnostics Laboratory expert cautions livestock producers to watch for deteriorating pasture conditions and the potential for cattle to consume toxic plants.

Of particular concern are four types of senna plants that can be toxic during different seasons and weather patterns: coffee senna, twinleaf senna, sicklepod senna and Lindheimer senna.  Dr. Tam Garland, head of the lab’s toxicology section in College Station, advises cattle producers to scout pastures and be on the lookout for these plants.

“Just like humans, cattle will want variety in their diet and they find the coffee senna beans quite tasty as forages become less available,” she said.

Ranchers should observe their cattle. Those excreting dark urine and having consumed coffee senna, and also twinleaf senna if there has been rain, will have clinical signs such as diarrhea and weakness before they get down

“It’s still important for ranchers to scout pastures and be on the lookout,” Garland said. “The biggest problem is we don’t notice subtle clinical signs in our livestock, nor do we scout our pastures and look for these potentially toxic plants.”