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50 Ways Farmers Can Protect Their Groundwater
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13. Conserve Beneficial Insects

lady beetle

Beneficial insects fall into a variety of categories, two of which are predators and parasites. Predators hunt and feed on pests, while parasites hatch inside or on a pest, and then they eat the pest as they grow.

Some companies sell predators or parasites for release in the field, but often they are expensive and ineffective. Your best bet is to conserve the beneficial insects already in your field. Keeping these bugs alive may help to keep pest problems at an acceptable level so you can reduce insecticide use.

conserving beneficials First, learn to recognize the difference between pests and beneficial insects. Then try to minimize insecticide applications, because many insecticides will kill the beneficials with the pests. Try to use selective insecticides that target a particular pest and use spot-treatment if possible.
conserving beneficials Maintain the habitat of beneficial insects by leaving crop residue on the ground and preserving woodlots, windbreaks, fencerows, and unmowed grassy ditch banks and waterways. Finally, provide pollen, nectar sources, or artificial food.
black cutworm Keep in mind, however, that maintaining habitats and providing artificial food do more than just attract beneficial insects. These strategies can attract pests as well. So carefully examine your yield goals and farming methods to determine whether you can afford a wide range of insects competing in your field.
a ground beetle—a predator Also, predators and parasites work slowly. And when pests become few and far between, the beneficial insects leave the field in search of more prey. So you are always left with a moderate number of pests still in the field.
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