By Dr. Mark Licht, Hugo Ramirez-Ramirez, and Brian Lang
Whether it's too much rain or perfectly timed rain, many fields are flooded or too wet to continue planting in many parts of Iowa. Delayed and preventative planting crop insurance dates are fast approaching with an unfavorable weather forecast. Decisions surrounding your delayed and prevented planting provision need to involve a conversation with your crop insurance provider. There is a nice article available on the Ag Decision Maker
website that talks about the insurance provision implications. Additionally, there is are articles addressing Late Corn Planting Options
and Late Soybean Planting Options
; these articles discuss late planted yield potential. Each choice has practical and economic implications; approach this decision with caution and armed with good information.
If prevented planting is taken, it is highly recommended to plant a cover crop or an emergency forage crop rather than letting the field be fallow through the summer. Please note; under prevented planted provisions a cover crop or emergency forage CANNOT be grazed or harvested for forage until after November 1 and cannot ever be harvested for grain without reduction to prevent plant coverage payment. Please discuss this with your crop insurance provider.
Annual Forage Crop Alternatives
There are three major concerns with the selection of forage options: 1) some options simply provide a cover crop; 2) some options can provide significant forage production during the summer or early fall at an expense to prevent plant payment; and 3) some can provide some aspect of grazing or harvested forage after November 1. Thus, the strategy of what to plant and when is dependent on the final objective. When considering crops for an annual forage, practical options include grazing, dry hay, stock piling, and silage (Table 1). There are many crops that may work as forage options, however, those listed in Table 1 would be the most practical, predictable, and economical. Seed supplies of some of these forage crops may be in short supply due to increased demand. As you consider these options, check on seed availability.
Table 1. Some species that would be suitable for emergency forage options as dry hay, silage, or grazing.
When considering forage species for prevented planting acres, review carefully what herbicides were used earlier in the spring in preparation for corn or soybean planting. Additionally, some herbicides from the prior growing season might have plant-back restrictions that need to be considered. Read and know restrictions on herbicides that you have used.
Foxtail Millet, also called German, Siberian or hay millet, is a summer annual grass; used as harvested or grazed forage. Plant through mid-July. Useable in about 50 days. One summer growth (vegetative 1-2 ft, with seed head 2-3 ft); best of the 'millets' for an emergency hay crop; can become a weedy grass if allowed to produce mature seed. Will terminate with fall frost, minimizing grazing potential after November 1.
Japanese Millet is a summer annual grass; relatively coarse (stemmy) forage; used as fresh cut forage, hay, silage or pasture. Plant through mid-July. Useable in about 50 days. Very little regrowth if first growth is allowed to reach maturity; if cut at vegetative growth stage, regrowth yields are more likely. Leave a 5 to 6-inch stubble height to maximize regrowth. Closely related to the grassy weed barnyard grass, so avoid allowing seed formation. Will terminate with fall frost, minimizing grazing potential after November 1.
Hybrid Pearl Millet is a multiple-cut, warm-season annual; used for fresh cut forage, pasture (rotational grazing is recommended), or silage; resembles sorghum × sudangrass hybrids in plant structure. Useable in about 50 days. Leave a 6-inch stubble height to maximize regrowth. Somewhat slower regrowth than sorghum × sudangrass hybrids; poor production in cool summer seasons; no risk of Prussic acid poisoning. Will terminate with fall frost, minimizing grazing potential after November 1.
The annual millets described above have been of particular interest.They are warm season crops and perform best in warm, sunny growing seasons. They have not performed up to expectation during cool, cloudy summers.
Sudangrass is a multiple-cut, summer annual; used for fresh cut forage, pasture (rotation grazing is recommended), or silage; difficult to dry thoroughly for hay; varieties vary in height and leafiness. Plant through early-July. The first growth is useable in about 50 days. At this late planting date you may get a 2nd harvest or grazing. Leave a 6-inch stubble height to maximize regrowth. Prussic acid poisoning risk is minimal but avoid pasturing severely drought stressed or very short (<18 inches) growth/tiller regrowth and use caution if grazing soon after frost. Will terminate with fall frost, minimizing grazing potential after November 1.
Hybrid Sorghum × Sudangrass is a multiple-cut, summer annual; used for fresh cut forage, pasture (rotational grazing is recommended) or silage; varieties vary greatly in height, leafiness, grain yield depending on the parent lines making up the hybrid. Plant through early-July. The first growth is useable in about 50 days, regrowth is from tillers. At this late planting date you may get a 2nd harvest or grazing. Leave a 6 to 8-inch stubble height to maximize regrowth. There is Prussic acid poisoning risk if plants or tillers are grazed or green fed at short height (<24 inches) or during severe drought and use caution if grazing soon after frost.
Sudangrass, and sorghum × sudangrass hybrids are better adapted than most species to drought, high temperature and low soil pH than corn but will yield less in seasons with cool August and September temperatures. Sudangrass and sorghum × sudangrass hybrids should be harvested at 2 to 3 feet of height (two to three cuttings per season). Harvesting at later maturity may increase yield but will result in lower forage quality. Will terminate with fall frost, minimizing grazing potential after November 1.
Grain Sorghum/Soybean Mixture can be planted through early summer. Harvestable window of about 70 to 110 days. Requires good fertilization for production. Generally, target harvest at late vegetative or very-early head stage of the sorghum.
Italian Ryegrass can be planted through August and would provide some forage for grazing in November. There would likely be a hard freeze before then, but still provide available grazing forage.
Berseem Clover is an annual warm-season legume that grows well in a wet summer. It requires a specific rhizobium for nodulation. Like alfalfa, first growth is useable in about 60 to 70 days. The seed is more expensive than other species. It is terminated with a killing frost, therefore, forage quality and quantity available after November 1 can vary significantly.
Teff is warm-season annual grass. It is a fine stemmed, leafy forage of good quality, but has had questionable success in Iowa. Dry-down for hay is difficult. A shallow root system makes it problematic for grazing. Good, rapid regrowth following harvest depends on leaving a stubble height of at least 4 to 5 inches. Will terminate with fall frost, minimizing grazing potential after November 1.
Spring Cereals (Oats, Wheat, Barley) can be planted in June or July as a cover crop, can be grazed about any time. Will likely head at a short height and shattering will occur. Can be cut and stored as dry hay or silage form late-vegetative through early milk stage. At dough stage, the stems decrease feeding value greatly. Oats is usually the cheapest option.
Winter Cereals (Rye, Wheat, Triticale) can be planted as early as June or July. They will remain vegetative through the season only reaching a height of about one foot. There is no stem production until it goes through the winter. Clipping winter rye in late summer is advised to ensure overwintering success. Winter triticale would be expected to respond similarly whereas winter wheat would likely experience winterkill. Suitable for grazing and forage.
Winter cereals planted in 2019 and harvested in the spring of 2020 can be ensiled and make good feed for young stock and even mature animals. When harvesting for silage, moisture content is critical. The target is similar to corn silage at 35% dry matter or 65% moisture. These forages tend to dry-down fast, so it is better to plan harvest when final dry matter is around 35%. Because of the structure of the stem, high packing density is essential for good fermentation. To achieve high density, harvest at boot stage and chop at ½ inch or shorter length. The use of silage inoculants is highly recommended for this type of forages.
Table 2. Forage planting date, harvest date, yield and quality of annual forages. Nutritional values may not be accurate for forage harvest after November 1. After Novemeber 1, forage samples should be tested for nutritional value.