Hemp Dogbane Control Tips For Safer Livestock

By Andi Anderson

Hemp dogbane and milkweed are common plants found in fields, roadsides, and pastures. They often grow together and look very similar, especially before flowering. However, both plants are poisonous to livestock and can cause serious health problems if consumed.

To protect animals, it is important for farmers to correctly identify these plants. Hemp dogbane has smooth leaves, thin stems that are usually red or purple, and produces a milky sap. It also branches near the top. In comparison, milkweed has thicker green stems, leaves with fine hairs, and does not usually branch unless cut. After flowering, milkweed forms upright pods, while hemp dogbane produces long hanging pods.

Although these plants can support pollinators like butterflies, they spread quickly through roots and seeds. This makes them difficult to control once established in fields.

Both plants are toxic to livestock. Animals can be affected by fresh or dried plant parts. Symptoms include vomiting, diarrhea, tremors, breathing issues, and heart problems. Horses are especially sensitive to contaminated feed. Poisoning risk increases when animals lack proper food or when contaminated hay is mixed into feed.

In grazing systems, animals can often avoid these plants. However, in hay production, it becomes difficult to separate them. Farmers should avoid chopping contaminated hay into small pieces, as this makes it harder for animals to sort. Long-stem hay allows animals to avoid harmful plants more easily.

Control methods include mowing and herbicide application. Mowing should be done early and multiple times to prevent seed formation. This weakens the plants over time. Herbicides can provide faster results when applied at the correct growth stage. Using a surfactant helps the chemical stick to leaves and work effectively. Farmers must always follow label instructions.

Complete removal is challenging, but regular management helps reduce risks. With careful monitoring and control, farmers can protect livestock and maintain healthier pastures.

FAQs:

1. What is the difference between hemp dogbane and milkweed?
Hemp dogbane has smooth leaves, thin red stems, and branching growth, while milkweed has hairy leaves, thick green stems, and usually does not branch.

2. Are hemp dogbane and milkweed harmful to livestock?
Yes, both plants are toxic and can cause serious health issues such as vomiting, tremors, and breathing problems if consumed.

3. How can farmers prevent livestock poisoning from these plants?
Farmers can manage grazing areas, avoid feeding contaminated hay, and ensure animals have access to safe and sufficient forage.

Photo Credit: gettyimages-diane-kuhl