Preparing for a successful corn silage harvest
Proper planning at harvest can help enhance yield, overall animal health and productivity throughout the year. A complete harvest management plan is the best way to ensure you have a successful corn silage harvest.
Here are some important items to consider when preparing for corn silage harvesting:
--Timing of harvest;
Jon Erickson, customer agronomist at Mycogen Seeds, says determining when to harvest can depend on weather, the type of hybrid, storage structure and other factors.
"Harvesting silage at the appropriate moisture content is one of the keys to success when producing a corn silage crop," Erickson says. "This step is critical, as moisture content will affect a lot of other processes that are going to occur later on in the silo."
Proper moisture content for conventional corn silage ranges from 65 percent to 70 percent. For brown mid-rib (BMR) silage the recommendation is 63 percent to 67 percent for upright/stave silo, 66 percent to 70 percent for a bunk or pit, and 66 percent to 68 percent for a bag.
"Remember that whole-plant moisture may be significantly less when you finish chopping than when you start. The most common mistake many producers make is chopping when the corn crop is past its optimum moisture," Erickson says.
Silage harvested when it's too wet loses soluble nitrogen and carbohydrates, he adds. This can result in low dry matter yield, large nutrient losses from runoff and poor fermentability--all of which can reduce feeding quality.
Silage that's chopped too dry may lose leaves and won't pack well, leading to less dense, more porous silage and aerobic microbial damage. Furthermore, starch can become crystalline, resulting in lower digestibility.
How do producers determine when the right time is to harvest? Traditionally, the kernel milkline has served as a guideline for harvest timing, with harvesting starting when the kernels are at one-half to two-thirds milkline. While a good "rule of thumb," this method is not accurate in every case.
Erickson recommends that producers utilize more precise ways to determine moisture levels. "One option is the Koster tester, which is a portable, forced-air electric drying unit. A microwave oven also can be an accurate tool of measurement and is relatively easy to use."
"Checking and preparing equipment prior to harvest is a must," Erickson says. "Anytime you don't have to conduct maintenance in the field is time that you've gained." Make sure all harvest equipment is in good operating condition. Chopper knives should be sharpened and set at the appropriate theoretical cut length, and kernel processor rolls must be in good condition.
Prior to harvest, clean storage structures of any remaining silage residue and make necessary repairs. "Fill those holes to prevent exposure to air that will affect the silage quality," Erickson says. It's a good idea to purchase any needed supplies ahead of time, including plastic and enough tires to completely cover and seal the silage pile.
Using these simple guidelines can help prepare for a high-quality forage crop. A harvest management plan that is properly executed can maximize returns for any producer.