Signs of Plant Poisoning in Cows
Not all plants poisonous to cattle will be lethal or make animals severely ill. It’s important to be on the lookout for any signs that your cows may have gotten into some toxic plants. Some are subtle, while others may be obvious:
Not eating at all or as much as usual
Losing weight
An overall unhealthy appearance
Muscle weakness
Failure to grow or develop normally
If your animals have any of these signs, there are also important indicators that the culprit is one or more poisonous plants. If your cows have been in a new pasture area, where the forage has been recently fertilized with nitrogen, or it is early spring and grasses haven’t come in yet, they could have gotten into some toxic plants.
What Plants are Toxic to Cows?
There are a number of toxic plants for cows, so it’s always a good idea to find out which grow in your area and to regularly check for their presence in your pasture. Here are some common plants toxic for cows, so you’ll need to remove these from pastures or anywhere they could have access them:
Black locust
Elderberry
Horse chestnut
Oak
Wild cherry, chokecherry
Arrowgrass
Bleeding heart
Buttercup
Dogbane
Foxglove
Iris
Jimsonweed
Monkshood
Lambs quarters
Lantana
Lupine
Larkspur
Locoweed
Mayapple
Milkweed
Nightshades
Pokeweed
Poison hemlock
Water hemlock
Sorghum
Tall fescue
White snakeroot
Any plants that have been over-fertilized with nitrogen
In addition to checking grazing areas for bad plants for cattle, some other management steps can reduce poisoning risk. Avoid letting cows overgraze areas, never turn cows into a new pasture when they are very hungry, provide plenty of clean water for cows, and fence off any areas that you know contain poisonous plants so cows can’t get to them.