Additional Considerations for Drought Stressed Pastures this Fall

Jeff McCutcheon, OSU Extension Educator, Knox County

Now I am worried. From measurements various graziers have been taking on a weekly basis the forage growth for September was flat. On several farm visits I came away with the impression that we were drier now than mid summer. The worry comes from knowing you need feed and knowing what the forages are doing this fall.

Fall is a critical time for our cool season perennial forages. In the cooler temperatures, leaf growth is slower while photosynthesis does not slow down. This increases the reserve carbohydrates in the plant. Cool season forages in the fall store reserve carbohydrates and use them to develop new tillers and roots. Carbohydrate storage, new tiller and root development can only happen if there is enough leaf area for photosynthesis. These three things are accomplished with little additional leaf growth. Making management decisions that negatively impact this development will hurt survival over winter and growth next year.

The first thing is keep from overgrazing. Overgrazing now could ruin next years forage production. Remember, overgrazing occurs when you keep animals in a field too long, or bring the animals back before the forages have recovered.

Overgrazing can be avoided by paying attention to forage residual, grazing time and rest. You should leave at least 1200-1500 lbs. of DM per acre or 2-3″ of green forage when you pull animals from a field. You should remove the animals before the forage starts to regrow. The pasture should recover to above 2400 lbs. of DM acre or 6-8″ before turning the animals into a field.

How can we avoid over grazing when we are running out of a limited supply of hay? One option is grazing corn residue as suggested earlier in this letter. Corn harvest has started and the residue that is left in the field is not a bad feed for about 60 days after harvest. Check out:

Another option is limit feeding corn. If you have to buy feed this is the least expensive option. Check out the next article from Steve Loerch.

We can help our pastures by fertilizing. Fall is an excellent time to apply fertilizer to our pastures. Fall is the time when most of our forage plants are growing roots, developing tillers and storing energy for winter. Proper soil pH and adequate soil nutrients will enhance forage competitiveness. Take a soil test and follow the recommendations.

Nitrogen can be applied in fall. Late fall applications of nitrogen, from October through November, will increase grass tillering, root growth, and energy storage. This will help with spring green-up and improve competition against weeds. Apply after grass growth has slowed, but before the plant has gone dormant. Use a low rate of 30 to 40 pounds of N per acre.