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50 Ways Farmers Can Protect Their Groundwater
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20. Control Weeds With Cover Crops

wheat field

Cover crops are often planted to reduce soil erosion during the winter and early spring. If you manage cover crops properly, they may also help reduce weed populations. How much weed-control benefit you get from cover crops depends on many factors, such as rainfall, temperature, and soil characteristics.

Some studies show that after rye and wheat are killed, they release chemicals that may reduce weed growth. If you kill them a few weeks before planting corn and soybeans in the residue, rye and wheat could help you fight weeds.

corn Other researchers are not sure that the chemicals in rye or wheat effectively control weeds. Also, some point out that the chemical released to fight weed growth can hurt corn. But most agree that planting in the heavy residue left by these grasses will reduce weed germination and growth, as well as provide good mulch for your next crop.
oats Oats planted in the fall can also reduce weed growth when crops are planted in its residue. But the protection is not as effective as with rye and wheat. The oats usually die over the winter and don't leave as much residue at planting time.

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