Noble Foundation's Pasture Demonstration and McMillan Research farms to evaluate activity on naturally occurring populations of western ragweed
One of the most common subjects that Noble Foundation consultants are asked about each spring is weed control in pastures. Devising a strategy for effective weed control depends on many factors including weed species and growth stage, weed density, soil fertility, pH, forage type, stocking rate or forage requirements, and proximity to sensitive crops.
If the weed density is low or is not limiting forage availability, then it does not meet the treatment threshold and treatment is not justified for production reasons. Often we are able to improve grazing or fertilizer management, which can keep weed density below the treatment threshold. However, in many cases herbicides are necessary to maintain infestations below that threshold.
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