Most conventional farms in the Midwest grow corn, alfalfa, or soybeans and either grow them continuously or rotate them depending on the year. Such farms quickly become dependent on chemicals to fertilize the soil and to kill various pests. Lately, there has been a big movement to become more sustainable in different methods of farming and some trends are showing how new technology and green initiatives are really changing the way farming is done.
Organic farms, which eschew all or most chemicals, generally rotate several crops. While conventional farms might rotate two crops with each other, organic farms rotate four or five. This has several advantages. First, it reduces the farmer’s reliance on chemical pesticides.
The various pests that feed on crops can generally eat only one or two types. Farmers who grow the same thing year after year are basically creating a habitat for the pest. Farmers who rotate crops disrupt the pest’s reproduction.
While corn borers might thrive the year that corn is planted, they and their larvae might not do so well if the farmer plants oats the following year
Multi-year crop rotation is also good for the soil. Legumes like soybeans and peanuts add nitrogen and other nutrients to the soil.
Farmers who plant such crops every other year need to use less fertilizer than farmers who do not.
Multi-year crop rotation enable farmers to grow a more diverse selection of crops, just like in the old days. About 100 years ago, farmers grew about 10 commercial crops in Iowa, including apples, cherries, and potatoes. Bringing back such crops, especially heirloom and other specialty crops, will allow farmers to market them as local produce. Farmers could also grow perennial grasses for bioenergy. Such grasses can be grown on poor land that won’t support anything else.
Cover crops or “green manure” are crops raised to protect and enrich the soil. Planting cover crops on soil that is currently not being used to raise other crops prevents erosion, and reduces the growth of weeds. Cover crops can be composted or plowed under when it’s time to plant regular crops. The plants used as cover crops are hardy and easy to grow. Clover, oats, hairy vetch, ryes, and buckwheat can all be used as cover crops. Pastures for livestock can also be grown with these types of cover. Varieties of clovers, hay, and grasses work to change the soil, the diet of the animals, and the field ecosystems. Places like Central Farm and Garden have different mixes of each that will vary fields and make for healthier livestock.
Natural Pest Predators
One of the problems associated with pesticides is that it often kills other creatures besides the targeted pest. Chemical pesticides can kill birds and bats which often feed on insect pests. Sustainable farming calls for the farmer to think of their farm as an ecosystem rather than a factory, and a healthy ecosystem has predators. An organic farmer will seek ways to make their farm hospitable to birds, bats, spiders and other predators that feed on agricultural pests.
Farming is an important industry to our country, and doing it right and more efficiently can help everyone from the farmer to the customer. New methods in sustainable crop rotation, and pest studies are doing more to keep crops healthy and farms green.