Is Wild Parsnip Toxic to Livestock


Wild parsnip is just one of many invasive weeds that we are seeing invade area roadsides, uncultivated fields and pastures. Wild parsnip is poisonous to animals whether it is fresh or dried and fed as hay. All growth stages of the plant are toxic to livestock, when eaten fresh or dried in hay. High concentrations of furanocoumarins have been found in the seeds as well.

Grazing livestock will generally avoid poisonous plants IF adequate forage of more desirable species is available. Poisonings most often happen in spring, before grass growth is adequate to meet animal needs, or during periods of drought when the pasture fails to regenerate quickly. But poisonings can take place at other times, too…Certain areas in, or adjacent to, pastures can contain a wide variety of non‐pasture plants. These areas include fencerows, barnyards and pasture field margins. They can be quite attractive to livestock, even when there is good pasture nearby. Some areas are more favorable to the growth of weedy or poisonous plants. Also, when livestock are introduced to a new place, they are unfamiliar with the setting. These animals may be hungry and willing to sample plants they would normally leave alone. Feeding hay, silage, greenchop or other good feed prior to turning animals into an unfamiliar pasture will reduce the animals’ tendency to consume them.

People sometimes toss clippings from poisonous ornamental plants around their property to their livestock. The yew bush is very poisonous and is a common cause of livestock poisonings.

Livestock poisonings tend to be only occasional events…usually not widespread. Poisoning should be suspected if: several animals in a herd or flock show -acute disorders of the central nervous system or digestive track without a fever but with weakness and rapid weight loss. Indications may include; sudden acceleration of heart beat, stomach and intestinal irritation, general distress, or repeated attempts to void feces.

Signs of plant poisoning may differ in intensity depending on: kind of plant, stage of plant growth, soil in which the plant is growing, amount eaten, amount and kind of feed eaten during the time the poisonous plant was in the animal’s digestive tract, and the animal’s tolerance to the poison. Overgrazing will result in weedier pastures, and could result in the establishment of poisonous pasture weeds. Simply keeping livestock out of known problem areas can be a very practical approach. It will also give you a chance to reduce or eliminate the problem plant species and get better pasture established.

Learn to identify poisonous plants.Learn conditions under which these plants can be poisonous. Develop a good grazing plan. Rotational or strip grazing allows desirable plants time for regrowth. Improved grazing techniques will allow grasses and legumes time for regrowth between grazings. This will also improve their ability to compete with undesirable plants.

Lack of water will make it more difficult for animals to metabolize and excrete any poisons they may ingest while grazing. If intestinal irritation due to poisonous plant ingestion takes place, dehydration can result. A good, fresh water supply can help minimize these problems.

Spot spraying or wiping with an effective applicator can be a practical way to control poisonous plants. 2,4‐D, a common selective broadleaf herbicide, may actually make treated plants more palatable to livestock before the plant dies and withers. Glyphosate is usually a good choice for spot treatment.

A veterinarian will want to know what type of problem plant an animal may have eaten. Weeds in this area that may be poisonous include; nightshade, black locust, brachen fern, chokecherries, cocklebur, horsetail, jimsonweed,lambsquarter, milkweeds, oaks, pigweed, hoary alyssum and wild parsnip.

This Information and more about Wild Parsnips is shared from Adams County University of Wisconsin Extension. 

Your browser is out-of-date!

Update your browser to view this website correctly. Update my browser now