goats．a farmer might use native grass or nonnative seeds．either way，it is important to establish good ground cover to avoid the loss of soil through erosion．
forage crops like clover and alfalfa could be planted．these members of the legume family provide high protein food for grazing animals．they also improve the quality of the soil．
most plants use up nitrogen．legumes put nitrogen back into the soil．forage crops also help reduce erosion of the soil．
but using marginal lands for grazing is not as simple as it might sound．cattle can damage forage crops by eating down to the roots．also，their weight crushes the soil．that can make the ground too hard for growing资源难易程度:★★★★★★★★★★★★★★★
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