Producers with cattle and growing corn have the option of harvesting some of their high moisture corn and earlage for their cattle.
What is Earlage?
Earlage is growing in popularity in The Northern Plains and is ensiled corn grain, cobs, and in some cases, husks, and depending on the harvest technique, parts of the stalk. Earlage is higher in energy than silage but can be harvested, stored, and fed much like corn silage. However, it does have lower energy than dry or high-moisture corn grain.
According to NDSU Extension, “earlage works well in a variety of cattle diets, including growing and finishing diets for beef cattle and feed for lactating dairy cows.”
Advantages and Disadvantages
There are advantages and disadvantages to harvesting earlage and they include:
- Avoid drying costs
- Earlage can be harvested before dry corn grain normally would be combined
- Harvesting the corn crop as earlage will increase the dry-matter yield by approximately 20 percent
- Earlage is very palatable and mixes well with other feeds and forages
- Harvesting as earlage provides a longer residue grazing window for cattle
- Disadvantages –
- If harvested late, the cob is low in digestibility resulting in a lower energy content
- Losses due to spoilage can be excessive if proper silage-making principles are not followed
- Earlage is often lower in protein than other grain products
Make sure the moisture content is 35 to 40 percent for the harvested material, and 60 to 65 percent dry matter. If the earlage is harvested while the corn is too wet, dry-matter yields will be reduced seepage losses will be higher. Spoilage can also occur if the corn is less than optimum moisture content, and will also not pack well.
Earlage can be harvested in a number of ways. The most common method is to use a snapper head on a harvester equipped with a kernel processor. This will ensure that the ear, cob, and husk are harvested. The kernel processor should be set to crack all the kernels and break the cob into small pieces. Another option is to use an all-crop header on a harvester and take the upper one-third of the stalk with all the ears. This option will produce lower energy and protein feed due to the presence of the stalk. Finally, some producers use conventional combines by setting the machines to break up the cob and return to the grain tank.
Bunker or Trench silos are the best storage options for earlage. Earlage going into bunker silos should be covered and packed using the same method as silage. Bunker silos are best when the feed rate and storage volume are high. All bunker or trench piles of earlage should be covered with plastic and kept fresh to reduce spoilage and losses.
Harvesting at the correct moisture content is the most critical factor in managing high-moisture corn. The optimal moisture content ranges from 24 to 33 percent. When harvesting high-moisture corn, consideration should also be taken for processing and storage conditions. Crop conditions can change quickly, so growers need to be prepared to fill storage facilities rapidly or be able to switch fields as conditions change. Some damage to the grain is acceptable because it still will need to be processed prior to ensiling.
Harvesting High-Moisture Corn
High-moisture corn should be ground or rolled prior to storage. Grinding or rolling and subsequent packing of the corn facilitates oxygen exclusion in the silo. For feeding purposes, rolling is the preferred method of processing (compared with grinding) because rolling will result in fewer fines and lower probability of acidosis due to rapid fermentation when feeding.
When it comes time to harvest large volumes of corn in a short period of time, bunkers or silos are the best options. Packing is done with tractors, which may be equipped with a dozer blade or front-end loaders. A minimum density of 45 pounds of dry matter per cubic foot is desirable for good-quality high-moisture corn. If corn had been harvested frozen or below optimum moisture content, lactic acid bacteria such as Lactobacillus buchneri should also be added. If there is substantial mold damage to the ears, an acid preservative may be warranted. Be sure to check with the manufacturer for data to support the efficacy claims. Also, all bunker, trench and pile structures should be covered with plastic to create an anaerobic environment and minimize spoilage. Plastic covers should be inspected periodically and any holes or tears repaired.
Harvesting both earlage and high-moisture corn can be used in a variety of beef and dairy cattle diets. Earlage is an excellent way to harvest and store a nutritious and palatable feed product economically. Take care when feeding high-moisture corn because it does have a faster ruminal digestion rate than dry corn. With careful storage techniques to reduce spoilage and shrinkage, these feeds offer a number of opportunities to capture efficiencies in an integrated livestock system.