No matter what type of grazing livestock you have, you likely have experienced time frames when you wished you had more forage available, especially during the summer slump period to help extend the grazing season. Having more forage available to graze or mechanically harvest helps to balance out dry matter needs and reduces the need to purchase additional forage.

That being said, it holds true that the more forage you have to graze, the less you have to feed. It's always easier on the bottom line to first maximize grazing days and then make sure you have enough feed for next winter. Maximizing grazing and minimizing feeding almost always lowers inputs.

Perennial forages should be utilized as much as possible because once they are established, they are fairly economical to maintain, but occasionally annuals can be very advantageous. One of the best ways to use annuals is to incorporate them into the rotation of a crop field. It can be done without much disruption to your normal cropping system and provides multiple benefits. It is possible to grow the additional forage for livestock needs, provide temporary cover, and even improve soil biology at the same time if managed correctly. Grazing annuals in the fall allows for a longer rest period for perennial forages for stockpiling, often with slightly higher yields due to the extra rest, which also helps to delay that final grazing until after forages are dormant. With a little planning, and sufficient moisture, weather and soil conditions, it is certainly possible to graze a lot longer.

If you can get crops harvested early, several cool season annuals can be planted and provide some forage that same fall depending on the species used and possibly also provide forage for the next spring. The extra forage — especially when it can be grazed — is sometimes a good incentive to utilize a slightly shorter season variety of corn or soybeans.

One of my favorite mixes for late summer planting is cereal rye or triticale, spring oats and a brassica such as turnips or radishes. The oats grow quickly with sufficient moisture along with the brassica and provide high quality forage. The cereal rye or triticale lays low generally for the fall — the rye especially more so than the triticale — and then takes off growing in early spring. Both time frames can be grazed or mechanically harvested. I would only mechanically harvest for two reasons: I know I need more winter feed when conditions may not be suitable for grazing or excess nutrients are present and need to be reduced.

Spring grazing of annuals, AKA cover crops, is possible. It must be managed to not cause any additional compaction problems and it must be managed to leave adequate live plant material behind. This live plant residual is needed for adequate cover for the conservation purposes and adequate leaf area available for termination.

Avoiding Compaction

To manage it correctly, the livestock should not be grazing under wet conditions. The key here is to not increase compaction - at all.

Livestock should not be left in any one area for a very long period. Ideally, livestock should be moved or allocated new forage every day. Livestock can remove vegetation very fast; a keen eye on what is going on is needed to make sure the forage is not overgrazed. Larger allotments can be utilized but expect slightly less efficiency. The annual forage being grazed should be checked every day, whether moving the livestock or not.

The best utilization and control are achieved by strip grazing the annual. Strip grazing is allocating out a set amount of forage that you know will meet the needs of the livestock for a set time frame and still maintain the required live plant residual after removing the livestock. This can be achieved with reels of poly-wire and step-in posts. Generally, you will want three sets (reel and sufficient posts) for the front fence, the back fence, and the fence for the next move.

Summer annuals fit into a cropping system very well after wheat harvests if wheat is in your crop rotation. Quite often, summer annuals are more feasible than double crop soybeans. If an annual forage is planted instead of soybeans, you usually increase diversity in the rotation. You also have good potential to improve soil organic matter and soil health, especially if you use a diverse forage mix that can enhance the biological diversity where it is lacking. Most forage crops also provide more erosion protection and cover than soybeans, especially when using species with good fibrous root systems. The value of the forage crop can easily exceed the value of the double crop soybeans and the forage crop may even boost the next season’s cash crop. A considerable amount of valuable forage can be raised from the harvest period of wheat until the following spring prior to the next cash crop. Quite often, a second annual mix, like a cool season mix, can follow the summer mix for fall providing subsequent grazing and harvest opportunities.

Soil Health Benefits

Anytime you are adding diversity to a crop rotation or to a forage system you are usually improving soil health. Soil is living and is a habitat that needs to be managed in order for soil microbes to flourish and provide those soil functions necessary for food and fiber production. We talk about the four simple principles for improving soil health and this is done by creating the most favorable habitat for the soil food web. Those four principles include maximizing continuous living roots, maximizing biodiversity, minimizing disturbance, and maximizing soil cover. Some people call cows the fifth principle. They are certainly the above ground livestock that helps support the “livestock” below ground. Livestock should be our main management tool when possible. The rumen is an excellent microbe source. Feed it correctly and it will feed the soil and plants back. Most nutrients are returned to the soil in a good grazing system. Cows turn forages into urine and manure which make those nutrients available in more forms.

Adding additional annual forages to a grazing system or a cropping system is usually a good thing. But it becomes even more important if you are trying to do some soil regeneration. On sites with very low organic matter or extremely low biology, the more we can diversify the plants grown there, keep living roots present and keep the soil covered as much as possible, the more we are going to improve it. Strip mined reclamation sites can be improved a lot faster by following the soil health principles, but especially from adding more diversity and ideally livestock. I’ve seen very poor strip-mined ground turned completely around in just a few years following these principles. For this purpose, you want to use as diverse a seed mix as possible.

Planning and management of annuals, especially on cropland, is important for the health of the field and the livestock. This is especially true if you are in a continuous no-till system. If you want subsequent harvest opportunities or additional benefits of cover, then it is very important to not graze or harvest until adequate growth is available and also maintain adequate residual for regrowth, if applicable. If wet, wait until soils are drier or frozen.

You also don’t want to leave livestock in one spot for multiple days. It is advantageous to allocate out these forages in small amounts and continuously move the animals to fresh allotments. This can easily be done with a temporary fence. Water is certainly still needed and should be made available to the livestock. Water tanks should be moved often to reduce compaction in the heavier used areas and trailing back and forth. Ideally, a perennial grass strip left along one side of the field is used for water and mineral use.

It is best to not feed any hay or supplements in the crop field. Doing so increases the chances of heavier used areas and compaction. Hay that is not utilized can cause soil moisture issues the following spring preventing the soil from drying out adequately and evenly. If annuals are grazed prematurely and are low fiber, the addition of some hay will help to slow down the passage through the rumen. This can be avoided by not planting annuals, especially monocultures, with high water content, and/or waiting until the best height or growth stage prior to grazing. If hay has to be fed, then unrolling the hay is the best way to spread out the usage area but it should be avoided if at all possible.

Just like cover crops, follow all Risk Management Agency (RMA) rules and guidelines when planting annuals on cropland.

Grazing Precautions

There are a few precautions that need to be mentioned and they certainly can easily be managed around with a little care. The two most frequently reported animal health problems associated with summer-annual grasses are prussic acid poisoning and/or nitrate poisoning. Prussic-acid poisoning can occur in sudangrass and sorghum-sudangrass hybrids. Toxic levels of prussic acid occur most commonly after a frost or during a drought. Nitrate poisoning usually occurs when high rates of nitrogen fertilizer are used and then a drought or sudden weather change occurs. High nitrate levels are especially found in the lower plant parts. We saw a little of this after the drought of 2012. The nitrate in plants harvested for hay does not dissipate as it cures, so problems can occur when the hay is fed. When turning livestock out on lush spring forage, especially lactating animals, supplement with high magnesium mineral-salt mixtures to reduce the incidence of grass tetany. This can also occasionally occur in the fall. If seed is treated with a fungicide or any other type of treatment, or a herbicide or insecticide was used for the prior crop, be sure to follow any grazing or harvest restrictions on the label. If in doubt or if you have any concerns, test prior to use. Consult the extension service for additional information.

Annuals can be a good addition to a grazing system but shouldn’t generally make up a high percentage of the forage base because of risk factors. Those include availability of seed, sufficient moisture at planting, and the cost effectiveness. Purchasing hay could be a better option for a cow calf operation, especially in dry conditions. I find them most advantageous when there are multiple purposes to fulfill. Plan now to incorporate annuals into your cropping system.

“Can we graze cover crops?” The answer is yes with an “it depends.” Most annual forages used for cover crops certainly can be utilized quite well by grazing livestock. If they have been cost-shared through a government program, then double check program guidelines and requirements prior to grazing.

It’s not about maximizing a grazing event but maximizing a grazing season! Keep on grazing!

Related Content:

NDSU Extension Provides Outlook for 2023 Grazing Season,

Timing is Critical When Grazing Cover Crops,

Rethinking Crop Rotations to Utilize Cover Crops as Annual Forages