Minimum or reducedtillage methods can actually spread perennial weeds. Repeated tillage controls localized patches but isn't viable economically or environmentally for large, entrenched perennial weed populations, especially on erodible slopes. Fall herbicide application followed by tillage, then clean-up tillage and herbicide application the following year, often is the most effective at controlling perennial weeds. For conversion of CRP fields to corn and soybeans, a combination of herbicide application and tillage should adequately control perennial grasses and weeds. Perennial grasses that survive tillage and herbicide applications make it difficult to convert CRP lands to small grain production.
Gophers eat mostly plant roots but also some above-ground parts, including alfalfa crown buds.
They often build their burrows in the most productive field areas that have the most available food supplies. They destroy vegetation directly over their burrows, creating thin plant stands or bare spots. Gopher mounding occurred in almost half of the CRP fields in the University of Minnesota survey. Although the degree of mounding is limited in most of these fields, severe mounding occurs in about 10 percent of the fields. Therefore, though not a major problem, pocket gophers could inhibit the future use of some fields if not controlled.