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Poisonous Plants on Rangelands

All Poisonous Plants on Rangelands Content

Field pennycress

Toxic Plants in Dormant Pasture and Hay: Field Pennycress

Toxic plants negatively impact livestock by decreasing reproductive performance (breeding and calving rate), reducing weight gains, and causing animal health issues and death. Assessing and treating animals experiencing toxicity may increase operation costs through either veterinary intervention or death loss.

From left: Meadow deathcamas in a South Dakota prairie rangeland. Silvery Lupine in a rangeland in South Dakota.

Poisonous Plants on Rangelands: Deathcamas and Lupine

With prolonged drought conditions throughout many areas of South Dakota, there is an increase of invasive weeds and poisonous plants on rangelands. Identification of poisonous plants is crucial to ensure livestock production is not compromised.

Three woody plants. From left: Ponderosa pine tree, chokecherry bush and greasewood.

Poisonous Plants on Rangelands: Woody Species

Several woody plant species that are poisonous to livestock are found throughout South Dakota rangelands, including ponderosa pine, chokecherry, greasewood and broom snakeweed.

Three poisonous rangeland plants. From left: Hemlock, Halogeton and Buffalo Bur.

Poisonous Plants on Rangelands: Hemlock, Halogeton and Buffalo Bur

Several species of poisonous plants are invasive and can easily establish dense stands when there is a disturbance on rangelands. Hemlocks, halogeton and buffalo bur can all be found throughout South Dakota and are toxic to livestock.

Two poisonous rangeland plants. Left: Woolly Locoweed.  Right: Lambert Crazyweed (Purple Locoweed).

Poisonous Plants on Rangelands: Locoweed and Crazyweed

Locoweed and crazyweed are found throughout South Dakota rangelands, and both can cause livestock poisoning.The names locoweed and crazyweed are often used interchangeably. However, there are notable differences between the species.

Low larkspur and twogrooved poisonvetch plants growing in rangeland.

Poisonous Plants on Rangelands: Larkspur and Poisonvetch

Larkspurs are the second leading cause for all livestock deaths from toxic plant poisoning. Poisonvetches are considered accumulator plants that uptake excessive levels of selenium and cause toxicity problems in cattle.