– Jeff McCutcheon, Knox County Extension Educator, Ag & NR
It is mid June and you are standing in a pasture field with the owner. The cows were rotated out of this field the day before. The ripening grass seed heads come up to your waist. The green leaves of the grass and clovers have, for the most part, been grazed to about 2 inches or 1200 lbs. of dry matter per acre. It does not look too bad. Yes, the spring flush got ahead of the owner, but with this year’s growth pattern, it was hard to keep up. The owner asks “Do you think I should clip this pasture?” In the following discussion you run through the reasons to clip pasture to see if they apply.
First, clipping will help keep it vegetative. Yes, but not at this point. It would have been beneficial to clip during the stem elongation or before flowering after the seed head emerges. That would have forced the plant to grow more vegetative tillers. This year that would have been in May. Now with the seed ripening on the stem those specific tillers are pretty much done. You will still have re-growth, just not from those tillers. Every cool season grass tiller in a pasture field does not produce a seed head every year. Two of my colleagues have said that clipping after flowering is either cosmetic or for revenge, not vegetative growth.
OK, what about weed control? Cutting weeds does more damage when the weeds are in bud or bloom stage. Walking in that pasture field, I did not see any perennial weeds in this stage. Clipping to control weeds could be a valid reason, but it needs to be timed right.
What about pinkeye prevention? One aspect of preventing pinkeye is to reduce eye irritation. A main eye irritant in pastures is seed heads and grass stems. Cattle will graze down through the seed heads and stems to get the more desirable forage. Seed heads and stems can cause physical abrasions to the eye. These abrasions provide an opportunity for bacterial infection. If you struggle with pinkeye, then clipping to remove the seed heads and get the stems below eye height is a valid reason.