March 28, 2008 

Green-up of warm-season pastures is usually a good sign in spring, unless the green is a weed problem.

Weeds remove moisture and nutrients from the soil that could be better used for later grass growth. Early weeds also can develop so much growth that they can shade, smother, and reduce early growth of your pasture grasses.

Herbicides and prescribed burning can control many early weeds, but I think another method actually is better - grazing. Heavy, pre-season grazing costs you nothing. In fact, you get some feed from these weeds while herbicides or burning would only kill and remove growth. Plus, this early pasture might be especially valuable if it saves you from feeding expensive hay.

Pre-season grazing will not harm your summer grass - provided you stop grazing before new grass shoots get more than a couple inches tall. This usually doesn't occur until late April or early May in southern Nebraska and slightly later further north in the state. Early, preseason grazing of warm-season grass also removes some old growth from last year, which starts recycling nutrients trapped in dead plant tissue. In fact, about the only bad news about early, preseason grazing is you have to get fences and water ready earlier, you need to move animals to the pasture, and you won't completely kill out these weeds in one year.

Funny thing, though. These so-called weeds might actually make pretty timely and valuable pasture. Give preseason grazing a try, I think you'll like it.

Bruce Anderson
Extension Forage Specialist