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About half of the earth's land surface has been converted to agriculture use. In some areas, including parts of Michigan, the figure is closer to 90 percent. The change of land to agriculture use began with the earliest of Euro-American settlers. After they realized the depth and richness of the prairie and savanna soils, these areas were cleared for agriculture, leaving only traces of the original plant community. Farming also occurred on cleared forest areas. Eventually some of these forest areas did begin to regenerate but were very different from earlier forests.
About three percent of the state's agricultural land, or some 250,000 acres, is currently enrolled in the Conservation Reserve Program (CRP), which is administered by the United States Dept. of Agriculture, Farm Service Agency (FSA) through their county offices. Land typically eligible for enrollment includes croplands susceptible to erosion that fall within conservation priority areas. Cost share money is often available to establish shelterbelts, shallow wetlands, and filter strips of grass or trees. Information is available from USDA offices, Conservation District offices, and Michigan State University Extension offices. Conventional Versus Conservation TillageConventional crop production practices that include moldboard plowing affect wildlife in several ways. First, they reduce and isolate the amount of natural habitat so that all that remains in heavily farmed areas are scattered remnant patches, wet depressions, and linear strips in a sea of cropland. Second, few native plants and animals adapt to, or can tolerate, heavily managed croplands. Third, the practices leave little food or shelter for wildlife during the winter months. The greatest impact to wildlife is the practice of fall plowing, which is often used with conventional tillage.
Conservation tillage causes less compaction of the soil, (compaction occurs when heavy equipment and implements cross the field over and over), which has a positive effect on the soil, allowing water to perculate into the soil instead of causing erosion and washing pesticides and fertilizers into the surface water. The soils better permeability also favors soil invertebrates. Invertebrates account for 90 to 95 percent of all animal species, and play a critical role in soil health. Growers need insects, spiders, worms, snails, and nematodes because the invertebrates act as decomposers, pollinators, soil conditioners, food sources for higher organisms, and control agents for other organisms, which may be harmful.
Large, open fields with no natural cover only attract a few bird species such as the brown-headed cowbird, horned lark, Vesper sparrow, and killdeer. Similarly, few mammals use these open fields, such as deer and white-footed mice, voles, and ground squirrels. Many more species--and as many as five times more birds--prefer the edge over the middle of such clear fields. Consequently, as field size increases, the proportion of field edge decreases and so does the average abundance of birds per field. Road-to-road farming operations that remove old fields, woody cover, and edge habitats can lead to a huge decline in the number and kinds of wildlife. Other Conservation-minded Farming PracticesMost wildlife depend on a number of habitat types for food and cover. Greater wildlife abundance and diversity are possible through management of the entire ecosystem rather than management of an individual area or species. For the greatest impact, consider the total picture--how croplands, forests, and wetlands can provide good living conditions to a variety of wildlife. If some food and cover types are available on nearby areas, best results may be achieved by providing an element of the habitat that is missing. Management is also more effective when neighboring lands are involved. Greater varieties of food and cover will result in more abundant wildlife. Here are several practices to consider. In addition, the Crop Fields chapter will have additional information.
Organic farming practices that rely on composting and manuring of fields may help improve the compatibility between crop and animal production practices and wildlife conservation. Organic farmers usually use less conventional tillage, avoid manufactured fertilizers and pesticides, have greater crop diversification, rely on crop rotations, and cultivate smaller fields. Field borders, shelterbelts, and fencerows between fields and around the perimeter of fields can help wildlife if the borders contain grasses, legumes, and fruit-bearing shrubs. The more
Hayfields will provide desirable plants used by livestock and preferred by wildlife. Lack of vigorous growth and an increasing amount of undesirable plant species that invade hayfields may be signs of low fertility, low pH, and a need for replanting. Burning, mowing, and grazing are three common practices to rejuvenate hayfields and retard natural succession. Burning and mowing should be done before April 15 or after July 15, so nesting wildlife will be spared. Separating pastures into units and grazing them alternately will prevent over-use by livestock and allow wildlife to nest undisturbed in unused units. Grass areas next to ponds and other wetlands, where wildlife naturally congregate, should be fenced off to protect water quality and nesting wildlife. A minimum of 100 feet of perimeter protection is recommended. Hayfields can be established with either native or introduced grasses and legumes. Lands that have been taken out of production are often planted with cool season grasses such as timothy or orchard grass, or legumes like ladino and sweet clover. Native, warm season grasses--switchgrass, big bluestem and Indiangrass--have their greatest growth in mid-summer and give landowners an option to continually mowing or grazing cool-season grasses and legumes. Planting a field of cool season and another with warm season grasses provides different heights and densities, which wildlife find attractive. Refer to the Hayfields chapter in this section for more information
In summary, even though your goal may be financial, studies indicate that new crop management methods increase your overhead while helping wildlife. Indeed, cropland management can be both beneficial to the landowner and to wildlife. The following chapters in this section explain a variety of management options that do just that. Last Revised: September 29, 1999 |
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