A wet fall in 2018, unusually cold temperatures this spring, excess rain and, in some cases, flooding have cattle and sheep producers wondering how to manage forage shortages this summer and produce forage supplies for next winter.
“The good news is there are haying, grazing and silage options,” says Beth Doran, Iowa State University Extension beef specialist. “But before a final decision is implemented, producers should check with their crop insurance agents about their alternative plans.”
According to Brian Lang, ISU Extension field agronomist in northeast Iowa, most short-term forages are fast-growing annual crops. Sorghums and millets are traditionally grown for summer forage; whereas, cereal grains and forage brassicas are popular cover crops for fall or early spring grazing, depending upon the forage species.
Choose forage type to meet needs
Each forage species has unique characteristics, such as growing season, size, regrowth potential, feed value, presence or absence of anti-quality components, yield and suitability for haying, grazing or silage. Check the Iowa Beef Center fact sheet for short-term and supplemental forages descriptions.
Prussic acid (an anti-quality component) may be present in sudangrass, sorghum-sudangrass hybrids and forage sorghum when plants are grazed or green-chopped at short heights (less than 18 inches for sudangrass; less than 24 inches for sorghum-sudangrass hybrids; less than 30 inches for forage sorghum); or during a severe drought, or if grazed too soon after frost. Remember, all annual forages can be high in nitrates if the season turns dry.
Best crop for emergency forage
Sorghums and millets are usually planted once soil temperatures are 65 degrees F and increasing, up to early July, and used during summer and autumn. They will be ready for first harvest or grazing about 50 days after emergence. Pearl millet and sudangrass are best-suited for grazing due to their rapid rate of regrowth. Do not cut or graze shorter than a 5- to 6-inch stubble height to encourage good regrowth.
For an emergency hay crop, foxtail millet would be the forage of choice due to rapid drydown, but plan for only one hay harvest. If harvesting silage, forage sorghum and corn are best based on yield and feed quality.
Teff new forage
Teff is a relatively new forage species that has very fine stems, rapid regrowth in midsummer and a high leaf-to-stem ratio. It can be harvested 45 to 55 days after planting and is most often used for hay. To encourage good regrowth, the cutting height should be 4 to 5 inches. Teff stores its regrowth-reserves in its lower stems, and a cutting height under 4 inches can be devastating to its regrowth ability. Grazing isn’t recommended due to its shallower rooting, especially early in the growing season.
What’s the best forage cover crop for fall grazing? “The species of choice for fall grazing cover crops is highly dependent on how early they can be planted,” says Joel DeJong, field agronomist with ISU Extension in northwest Iowa. “For fall grazing, most cover crop species such as cool-season annual grasses, cereals and brassicas yield more forage when planted midsummer. If planted after early September, cereal rye and triticale, which is a cross of wheat and rye, are better-suited for the shorter growing season.”
Doran says cereal rye has a couple advantages. It will overwinter and is one of the earliest cover crops to appear in the spring. Because of this, it is often used for early spring grazing and a clean, green area for cow-calf pairs after calving.