When to use that fescue
One question that beef producers might be asking regarding stockpiled fescue is; when should stockpiled fescue be utilized? If fescue was last grazed, clipped, or harvested for hay in early August and has been stockpiling since that point, a considerable amount of plant material will have accumulated by the time the growing season ends and plants go dormant. Work done in Ohio suggests that if stockpiling was started in early August with 50 units of nitrogen applied around mid-August, and assuming normal precipitation, it is not unreasonable to accumulate more than a ton and a half of dry matter, in fact, 3500 to 3700 lbs./acre could be available. Even without nitrogen fertilization a ton or slightly more dry matter could have accumulated. Most cattlemen I have talked with regarding stockpiled fescue say they like to wait until after a couple of hard frosts before turning cattle in to the fescue because cattle will graze it better. This brings up a question of when to begin grazing stockpiled fescue.
Much of the tall fescue in our area is infected with an endophyte, a fungus that produces a toxic substance known as ergovaline. The endophyte and ergovaline are responsible for the reduced palatability of fescue during the summer months. The fescue toxicosis associated with ergovaline is responsible for elevated body temperatures, restricted blood flow to extremities and poor animal performance. It has been generally assumed that ergovaline doesn't pose a problem in stockpiled fescue, in part because the ergovaline seems to concentrate in seed heads and stockpiled fescue is vegetative. Yet, the fact that cattle don't really eat stockpiled fescue well until after a couple of hard frosts suggest there are still concentrations of ergovaline present in infected fescue that reduce palatability until after frost.
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