Excessive grazing to an extent that the land is damaged.(noun)
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Use "overgrazing" in a sentence
"Now that wolves are back, the overgrazing is being limited and trees are once again able to grow to that critical height."
"In my view, the Fed on the whole acts very cautiously when establishing Federal land use, and to some degree (such as overgrazing in New Mexico) not strongly enough."
"Nonetheless, Yamal Nenets are currently showing signs of stress adapting to the recent barrage of simultaneous changes in their homeland – from health and demography  to questions of land tenure  and increasingly severe "overgrazing", predation, and poaching on reindeer pastures ."