Harvest time: Watch your moistures
Posted on August 6, 2012 in Dairy Performance
By Chris Wacek-Driver We’re already starting to chop corn silage in some parts of the Midwest. As you look to harvest this year’s crop, we once again remind you of the importance of closely monitoring your moisture levels. For corn silage, we recommend an optimum moisture level of 65 to 68 percent, but you’re generally in good shape if you fit into the 62- to 68-percent window. Remember, you can’t judge moisture content by looking at the plant. The best, most accurate method is to send in samples to a lab if you know you can get a quick turnaround. Most seem to be able to get results within 24 hours dependent on mail time. If sending in the sample is not an option, you can check moisture levels using a koster forage moisture tester or microwave. Finely chopping your sample will boost accuracy with this method. We see a lot of variation across fields this year, so it really can be difficult to judge moisture levels with just a few plants. Get a chopper in the field to get a good sample and an accurate measurement. It’s important to keep your custom harvester informed of your moisture content so that you can better schedule your harvest time. Too wet The biggest problem with not watching moisture levels is we run the risk of putting up forages that are too wet. The problem with that is two-fold. First, runoff is an issue. You can lose a lot of nutrients, including highly available energy in the form of sugars. Second, fermentation under these conditions often produces very acidic forages, particularly high in acetic acid. Cows don’t do well on silage with high acetic acid because it is sour, unpalatable and may cause production and health issues. Drought-stressed plants can pull up a significant amount of moisture after rain. Moisture levels can increase by as much as 5 to 6 percent. Nitrate levels can also jump after rains. Therefore, it’s best to wait three to five days after rain if you can. Too dry Close to harvest, moisture levels can drop quickly. In a normal year, we usually see a 0.5- to 1-percent drop per day. In droughts, it can decrease by 2 to 3 percent each day, especially if it’s hot and windy. Although unusual, I’ve even seen drops of 5 to 6 percent. The catch with dry silage is that it will hold more air in the bunker or pile. Therefore, our recommendation is to chop finer if it’s too dry. Think about adding an extra packing tractor to increase the density and get out as much air as possible. In addition, consider treating the silage with Crop-N-Rich Buchneri or Crop-N-Rich Stage 2 inoculant to boost aerobic stability. Finally, we sometimes see smaller, harder kernels under these conditions, so double-check that your kernels are being adequately processed. You may need to turn down the roller to achieve adequate processing. Conversely, if there is a lack of corn in the silage, you may be able to open up the processor and let the knives do the work, rather than the processor. Inoculants This year, it’s especially important to use a good upfront inoculant, such as Crop-N-Rich with MTD/1, as UV light reduces natural bacteria levels in the fields. You want to ensure you have enough organisms on the silage to provide good fermentation. Furthermore, a good fermentation reduces potential nitrates. Working smart This drought has certainly stressed systems, producers and support staff. As always, please remember to slow down and make safe, rational decisions as you approach this year’s harvest. Please contact your Vita Plus consultant or dealer with any questions you may have on forages, inoculants or other topics. About the author: Chris Wacek-Driver is the Vita Plus forage program manager. She grew up on a farm outside of Denmark, Wis. and attended the University of Wisconsin-River Falls where she earned her bachelor’s degree in dairy science with an ag business minor. She went on to receive her master’s degree from UW-Madison. She conducted her research focusing on forage quality at the USDA Forage Center under Dr. Larry Satter. In particular, she studied forage fermentation, the role of microbial and enzyme additives, and their effects on dairy animal performance. Wacek-Driver has been a Vita Plus employee owner for the past 21 years and worked in dairy technical services prior to her current role. She has a passion for working with dairy producers to help them with on-farm feed inventory, feed management, forage fermentation and production, and dairy nutrition. She resides on a 240-acre farm along the bluffs of the Mississippi River in western Wisconsin.
Forage storage and management