Silage Harvest Options for a Wet Fall
Fall has arrived in the Northern Plains and Midwest; however, with many saturated fields, some producers are growing concerned that there will be little to no opportunity to harvest silage before corn dries down past desired moisture levels or frost occurs. There is no easy fix to a ‘missed’ silage cutting, but there are a few options to consider.
Creating quality silage is most dependent on harvest plant moisture. Ideally, when chopping silage, kernels should be 1/3 to 2/3 down the milk line and on average, 32-38% dry matter (Akins, 2018). Harvesting at over 40% dry matter reduces digestibility of fiber and starch, and also causes packing issues. More specifically, the optimum silage moisture ranges from 55-60% for upright oxygen-limiting solos, 60-65% for upright stave silos, 60-70% for bags, and 65-70% for bunkers (Bernhart, 2018). In other words, wetter silage tends to work better in bags, bunkers, and piles for better packing; dryer silage tends to work better in upright silos to minimize seepage. For information on calculating dry matter view Moisture the Critical Component to Good Silage.
There are still a few options for farmers who want to produce wet feed this year and are growing concerned of corn drying down too quickly. Equipment availability and plant moisture should help determine what works best on your operation. If precipitation continues, famers may have to wait until freeze-up to enter some fields.
Chopping Dry Silage
Although not ideal for optimum feed value and storage, if a producer chooses to chop silage above 40% dry matter, there are several considerations to make:
Reduce chop length to release more plant fluids and improve packing.
Use a kernel processor to improve digestibility- the more mature the corn the less digestible it becomes.
Use silage inoculants to improve fermentation. Liquid inoculants may be more effective in dry silage.
If piling or using bunker silos, use extra heavy tractors for packing and pack no more than 6 inches at a time.
Blend wetter feeds with your dry silage like forage sorghum, alfalfa, or later-planted green corn.
Place your wettest forage on the top layer of the pile or horizontal bunker for sealing and weight. Adding water to the top layer of the pile may also help with this.
Cover tightly with silage plastic and/or oxygen barrier to keep the environment as anaerobic as possible.
Some producers may choose to add water as they pile or fill silos; however, it takes approximately 7 gallons of water for every ton of silage to raise moisture content 1 point and corn plant material absorbs water quite slowly. Therefore, a large amount of water would be required at a very fast rate to keep up with most silage harvest processes, making wetting nearly impossible to render major results.
Remember that dry silage can often heat and mold, lowering protein digestibility and energy; this happens mainly due to oxygen embedded in the silage due to poor packing.
Earlage is defined as ensiled corn grain, cobs, and in some cases, husks and a portion of the stalk depending upon harvest method (Lardy, 2016). With an energy content higher than corn silage but lower than corn grain and a similar protein content to corn silage, earlage makes a good alternative. Ideally moisture content is 35 to 40% (60-65% dry matter). A silage chopper with a snapper head can be used. Other producers have successfully used combines set to retain a portion of the cob with the grain. Much like silage, if harvested too wet, seepage may occur; if harvested too dry it will not pack well which will cause excessive spoilage. Things to consider when chopping earlage:
Make sure that every kernel is cracked and that the cob portions are no larger than a thumbnail to improve pack density and digestibility.
Consider using a kernel processor to improve digestibility.
Use inoculants to improve fermentation.
If piling or using bunker silos, use extra heavy tractors for packing.
Cover tightly with silage plastic and/or an oxygen barrier to keep the environment as anaerobic as possible.
Baling Corn Residue
Although removing all corn residue off of a field in the late fall is hard on soil health (much like chopping silage), if an operator feels it is their only option, harvesting corn for grain and baling corn residue may be a viable feed option. Corn grain and corn stover can be ground and mixed into feed rations as an alternative to feeding corn silage. Contact an animal nutritionist for assistance creating a total mixed ration. If at all possible, plan on returning manure with or without bedding to these fields to help replace soil organic matter.
This practice can be accomplished successfully, but it requires intensive management and involves livestock health risks if not carefully monitored. Strip grazing and/or limit feeding are both important parts of grazing corn fields. For more information on grazing standing corn see the OSU Using Corn for Livestock Grazing fact sheet.
Swath grazing is sometimes a good alternative to grazing standing corn. In this process the producer swaths the standing corn or corn stover and allows mature cattle to graze throughout the winter.
Nitrates can be a concern if the corn crop was under stress, particularly drought. Grain overload or founder is a greater concern. If access is not strictly controlled, cattle run the risk of severe digestive upset or death due to consuming too much corn at one.
Again, swath grazing the entire corn plant requires intensive management. Implementing this strategy should be planned carefully and in most cases is a last resort if all other options to salvage value are not feasible.
Baling the Entire Plant
Although not recommended, baling standing corn can be accomplished in some cases. According to Bruce Anderson, UNL Extension Forge Specialist, whole plant dry matter levels should be at 80%+ when baling. Stalks should be conditioned or cut with a rotary mower to allow moisture to escape. Getting stalks dry for baling, keeping bales tight, and avoiding ear molds in this case can be very difficult. If a producer does bale standing corn it is best to feed bales quickly to avoid storage problems.
What to Watch For
Flooded corn can contain many contaminants. Watch for corn ear molds, stalk molds, and if the plant is quite dirty, soil contaminants. Preservatives and fermentation do not lower the concentration of these toxins in your feed. If you have concerns or have seen any of these issues in the field, first consider identifying ear or stalk diseases. Then, contact your crop insurance agent to determine the right procedure. For more information on moldy corn and silage concerns view Moldy Corn and Corn Silages Q&A.
Pricing or Buying Feed
If it becomes necessary, use the Silage Earlage Decision Aid for help pricing silage or earlage in South Dakota. Alternatively, use the Feed & Forage Finder for help finding feed for sale in your area.
This has been a challenging year with heavy spring precipitation and now extensive fall precipitation in some parts of southeastern SD. Remember, all hope is not lost for your silage crop- keep the options above in mind and have a safe harvest this year. For more information about harvesting corn as a forage, contact an SDSU Extension expertnear you.
Resources and References:
B. Anderson, 2015. Making Silage out of Dry Corn.
M. Akins, 2018. Corn Silage Harvest Management.
S. Bernhart, 2009. Harvesting High-Quality Corn Silage.
E. Byamukama, 2018. Stalk rots Developing in Corn.
T. Erickson, 2017. Mycotoxin considerations for Weather-Damaged Feedstuffs.
T. Grussing, 2018. Silage Harvest Plans.
J. Hoorman, C. Little, J. McCutcheon, 2003. Using Corn for Livestock Grazing.
G. Lardy, 2016. Harvesting, Storing and Feeding Corn as Earlage.
D. Schwab, 2018. Silage Making with 2018 Weather Challenges.
C. Strunk, 2011. A Closer Diagnosis: Corn Mycotoxins.
Fri, 10/05/2018 – 10:34
Source: Dairy Herd