Grass and hay diversity is important for farmers to have on their land. Depending on what kind, some grasses have more nutrients than others. Alphalpa hay is high in nutritional value, but if animals have too much they can get over weight. It is also expensive to grow. On our land we had Dallisgrass, Coastal Bermuda, Bahia, in addition to Fescue. These are good cattle grasses because they are cheap and maintain them selves without much irrigation if any. However, Georgia is an extremely humid state. It rains a lot there as well. This is why we do not have to irrigate as much as other states. If you do not have a variety of grasses animals will develop a vitamin deficiency as do humans. According to Science Daily, grass diversity is better drought resistant. This can also contribute to farmers wallets by saving on their water bill.
http://www.sciencedaily.com/releases/2012/08/120808121920.htm
http://invinciblellama.wordpress.com/llama-fields/
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