Mid-August through early September is the perfect time to rejuvenate thinning alfalfa fields, says Bruce Anderson, forage specialist with University of Nebraska Extension.

Most alfalfa fields begin to thin out after a few years, so Anderson suggests interseeding grasses to hay an alfalfa-grass mix or convert the fields to pasture.

“Not only might you extend the useful life of your alfalfa field by several years, you also will develop excellent hay or grazing for your livestock,” he says.

Orchardgrass is most commonly interseeded into alfalfa, but meadow brome, festulolium, endophyte-free tall fescue and wheatgrasses also can be used, Anderson says.

“In fact, if the field will be used as pasture, a mixture of several grasses may be best since it adds diversity to your animals' diet.”

If there is enough moisture to give new seedlings a good start, interseeding after an August or September cutting is recommended. “Alfalfa regrows more slowly this time of year, so it won’t compete with your new grasses as aggressively,” he notes.

By the next spring, growers can check how well the new grasses have established themselves. “If they seem a little weak, cut hay real early to open the canopy for better light penetration. After that you should be able to hay or rotationally graze as you choose.”

Contact Anderson at 402-4742-2577 or banderson1@unl.edu.