Summer Annuals for Grazing

Jeff McCutcheon, Extension Educator, Knox County

It is the first of June and grass growth has slowed or stopped. You are grazing through your fields and considering your options. One option to consider is planting summer annuals for grazing in mid to late July.

If there is any land not planted in corn, we could still plant something that could be grazed in 45-60 days. Of course corn is a grass and could be grazed but that is a whole different subject. What options are there?

According to the Ohio Agronomy Guide, we have the options of Sudangrass, Sorghum-Sudangrass and Millet.

Sudangrass is a fine-stemmed, leafy summer annual grass that can grow between three to eight-feet tall. It will regrow after grazing until a killing frost. Sudangrass usually contains lower levels of prussic acid and is usually lower yielding than the other sorghum family grasses. Do not feed to horses.

Sorghum-Sudangrass is a hybrid cross, although there are multiple varieties available. They resemble Sudangrass, but are generally taller, have larger stems and leaves, and are higher yielding. Sorghum-Sudangrass hybrids regrow after each grazing with proper environmental conditions. These can contain prussic acid. Brown mid rib varieties have shown higher animal preference and performance. Do not feed to horses.

Pearl Millet does not produce prussic acid. It tends to have smaller stems and more leaf than the Sorghum grasses. Pearl Millet regrows after each harvest, but not as rapidly as Sudangrass or Sorghum-Sudangrass hybrids. Fertilize all three according to soil test results similar to corn with a target of 100-150 bu. They can be no-tilled or broadcast into a prepared seed bed. Plant each at a rate between 25-30 lbs. to the acre. All of these summer annual grasses can be grazed or even cut for silage. These summer annuals should be grazed after they are 18-inches tall. Grazing earlier has concerns with prussic acid and will weaken the plants. Trampling and wastage will increase when grazing is delayed past the boot stage. Plants reach the grazeable height of 18 to 30 inches about six to eight weeks after planting. Rotational grazing or strip grazing management should be practiced. A high stocking density should be used to graze the grass down in less than 10 days. Clipping leftover stems down to 8 inches will improve forage quality for the next grazing period.

Another summer annual not mentioned in the Agronomy Guide is Teff. Teff is a summer annual grass from Ethiopia. It can grow well in low moisture conditions. It is a fine stem grass that can be grazed in about 50 days and re-grazed about 45 days after the first grazing. Plant it at a rate of 4-5 lbs. to the acre. Use 50 lbs. nitrogen as a starter. Check out the factsheet from Cornell University for more information: http://nmsp.cals.cornell.edu/publications/factsheets/factsheet24.pdf