Before planting on CRP acres, scout the fields and determine what's there. The moral is plan ahead.
Many weed control problems face produc ers in returning to production land idled in the Conservation Reserve Program. Weeds largely have been permitted to grow and reseed themselves which compounds problems in the 10 years land has been in CRP. Some CRP fields were established hurriedly at minimal cost and effort and now have thin grass sods, weeds, and brush which need to be addressed.
One of the first things to be done in planning to crop CRP land is scouting fields to determine what's there and what should be done to get ready for cropping. The moral is plan ahead.
Keep in mind that cool-season grasses may require different control than brush and tree saplings and that weed control measures for some crops are different and require more effort than for some other crops. Also, weed control for no-till systems is different than for plowed ground.
Control success is best achieved in the fall prior to planting the following spring. Release dates from CRP contracts are important in weed control prior to crop establishment. If a contract expires Oct. 1, the ideal time to begin weed control would be the previous Aug. 1. U.S. Consolidated Farm Services rules on CRP lands state cover may be destroyed in the last 90 days of a CRP contract to prepare seedbed for fall-seeded crops if performed according to an approved conservation plan. But, before starting control measures prior to CRP contract expiration dates, producers should seek permission from their local Consolidated Farm Services committees. Decisions will be determined on a case-by-case basis.
Starting weed control by Aug. 1 would help get rid of old growth sod and weeds, forcing them to regrow. Then by mid-September when regrowth has reached 6 to 12 inches in height, spraying glyphosate at labeled rates should provide good kill and make the land ready for spring planting.
If there is a lot of woody brush, such as multiflora rose and tree saplings, mowing probably is not an option. Use of herbicides in May or June prior to planting is recommended. Again, permission may be needed depending on CRP contract release dates.
Because much of CRP land is highly erodible, tillage might not be an option even though plowing would be ideal for getting rid of weeds and brush.
For Indiana's two principal crops, corn might be the better option because there are more options to control broadleaf weeds in corn than in soybeans. Beans might work, but planting may have to be delayed to burn down what weeds come up in the spring even though control measures had been applied the preceding fall. Weed control on CRP land preparatory to planting wheat and other small grains is similar to that for corn and beans.
Producers most likely will have to plow before attempting to establish the first wheat crop and other small grains.
Before beginning a grazing system on CRP land, take care of weeds and brush problems. Once weeds are under control and optimal fertility levels are reached, good grazing management will help maintain fertility while decreasing or even preventing further weed problems.
However, good management alone normally will not correct serious pre- existing weed problems. Plants such as thistles, brush, and perennial broadleaf weeds may continue to be a problem even before grazing of CRP fields begins, since they seldom are eaten even at high stocking rates. Remember that different kinds of thistles require different control measures.
Also remember that not all plants considered weeds in row crops are problems in pasture. These include quackgrass and lambsquarters which are very nutritious at certain growth stages and need not be removed. Be concerned mainly about those plants your livestock avoid eating, that are poisonous or that have low nutritional value. These include thistles, goldenrod, and vervain.
Mechanical and chemical methods and cultural practices are ways to control weeds in pastures. Repeated mowing, clipping, and hand cutting can reduce weed infestations. Tillage can be used, but is seldom necessary to manage weeds in a good pasture. If mechanical control is unsatisfactory in initial control, herbicides may be needed. But keep in mind that most pasture herbicides will remove desirable legumes as well as weeds. Frequently weeds are patchy, making spot spraying the preferred method of control over the more costly method of broadcasting.
Cultural practices help maintain weed-free pastures. Good grazing management with rest periods for the pasture and good fertility help keep forages healthy and able to compete with weeds. To prevent spread of weed seeds, avoid applying manure contaminated with weed seeds; clean equipment after use in weed-infested fields; and keep fence rows free of problem weeds.
CT-5 - Weed Control in No-Tillage Systems
WS-16 - 1997 Weed Control Guidelines for Indiana
Source: Daniel J. Childs 494-6474
Keith D. Johnson 494-4800
Ellsworth P. Christmas 494-6373
Ron Birt, Indiana Consolidated
Farm Services office
317-290-3030 Extension 205
New 9/95
Cooperative Extension work in Agriculture and Home Economics, state of Indiana, Purdue University, and U.S. Department of Agriculture Cooperating; H. A. Wadsworth, Director, West Lafayette, IN. Issued in furtherance of the acts of May 8 and June 30,1914. Purdue University Cooperative Extension Service is an equal opportunity/equal access institution.