Grass Silage Tips
Updated: Jun 23
Bill Eberle, Key Account Manager
If 2020 has taught us anything, its that just when we think the dairy industry couldn’t possibly see any more challenges, life says “Hold my beer.” At this point, I wouldn’t be surprised if life on Earth gets wiped out by a swarm of locusts. As dairy farmers face the corona virus milk price depression, after 3 years of already subpar milk prices, spring has brought us alfalfa stands that look like a Bob Ross shaped Chia Pet having been marinated in a bath of gramoxone, 2-4-D and Roundup. Some of the dairies I work with in Eastern Wisconsin will be tearing up 100% of their alfalfa stands after having struggled with winterkill in 2019 as well. Many of them will be interseeding various grasses into existing stands as a way of salvaging something out of those fields and having something in the bunker to feed in early summer.
While adding grasses into poor alfalfa stands is a viable way of increasing yields, it doesn’t come without challenges. When last year’s winterkill led dairy managers to interseed grasses, in some cases they ended up with mold issues in their piles and bunkers after the alfalfa/grass silage had been ensiled. What was so surprising to me was that I observed this on dairies that do an impeccable job of forage management and rarely have issues in their feed pile – these are farms that usually have above average packing densities and forages harvested at the correct moisture.
That being said, what we found with one mold issue was poor compaction (only 13.5 dry matter pounds per cu ft) and feed that was not in the ideal moisture range, especially near the top of the pile. The dairy owner immediately asked “How can we not have good density? We had the same number of pack tractors that we always do?” That was true, they did have the same number of pack tractors, but this year was different in that there was a substantial amount of grass mixed in with the alfalfa.
The other issue was the dry matter level. At 46% dry matter, it wasn’t really that far outside the ideal range for alfalfa. A pile of alfalfa haylage with good compaction that’s 46% dry matter should ensile and ferment well, especially if its inoculated with a sound inoculant like the ones in the SILOSOLVE® line. However, grasses ensile better at lower dry matter levels, ideally around 40% dry matter.
The whole challenge of ensiling these grass/alfalfa mixes reminds me of the early days of industry expansion and learning how to now harvest hundreds of acres of haylage per crop instead of 80 when the average farm size was substantially smaller. We had our growing pains and we had to learn as an industry how to manage harvest differently.
Tips for ensiling grass/alfalfa mixes:
1. Establish who is responsible for the decision making. One person should have the final say in when we start, when shut down, when we switch fields, etc. When everyone’s in charge it means nobody’s in charge
2. Pay attention to windrow width. Grass dries far faster than alfalfa, a wide windrow of grass laying in the sun will dry out very quickly beyond the ideal range.
3. Use field cut order to your advantage. Cut the grassiest fields first so they’re on the bottom of the pile as opposed to the top where compaction is the most challenging
4. Pack like your life depends on it. If 800 pounds of tractor per ton of feed coming in is normally adequate, shoot for 1000. No exceptions.
5. Use a science based, research proven inoculant like SILOSOLVE®MC that helps mitigate clostridial fermentation when feed is ensiled too wet to get a jump on harvesting before the silage harvested late in the day dries beyond the ideal range.
Interseeding grasses in alfalfa stands can undoubtedly be a way of salvaging some poorer alfalfa stands as long as it is understood that it doesn’t come without its challenges and the need for a heightened level of forage harvest management.