By Andi Anderson
Warm temperatures and steady rainfall this spring have sped up the growth of grasses, legumes, and various weeds. Two toxic weed species drawing concern are poison hemlock and cressleaf groundsel. Both can pose risks to livestock and need careful management.
Poison hemlock is a biennial weed that grows without flowering in its first year and blooms in the second year on stalks 6 to 10 feet tall. It is commonly found along roadsides, ditches, and field edges. All parts of the plant are poisonous to all livestock types if eaten.
Early control through mowing or herbicides leads to better results. Poison hemlock resembles Queen Anne’s lace but is larger, taller, and has purple spots on its stems. Other toxic relatives include wild parsnip with yellow flowers and giant hogweed. These plants all have umbrella-shaped flower clusters.
Control methods for poison hemlock include aggressive mowing to stop flowering and seed production or applying herbicides such as glyphosate, 2,4-D, Remedy Ultra, or Crossbow. Treatments are most effective when plants are less than 2 feet tall.
Cressleaf groundsel belongs to the aster family and shows yellow daisy-like flowers on hollow stems with a purple tint in spring. It is a winter annual, germinating in fall, growing through winter, and flowering in spring. All parts of this plant are toxic fresh or dried. If allowed to produce seed, it will return in larger numbers the next year.
Cressleaf groundsel is common in fields with bare soil during fall and spring, such as crop fields, but can spread to pastures and hayfields nearby. Fall herbicide treatments with 2,4-D products work best. If plants are already flowering, mowing and removing plant debris helps prevent livestock from eating the toxic plants and reduces seed spread.
Early identification and timely management of these weeds are key to protecting livestock and minimizing weed populations on farms.
Photo Credit: gettyimages-dszc
Categories: Ohio, Rural Lifestyle, Farm Safety