Feeding green grass to dairy cows is nothing new, but recent innovations have made it easier to add to diets of high-producing cows.
A new practice utilized on several large dairy farms in Wisconsin is proving efficient for harvesting high-quality perennial grasses to add to a TMR for improving cow health and performance, and manure or slurry can be used to fertilize the grass stand after each harvest.
Luke Wilson, market development manager at Barenbrug seed company, says using improved varieties of grasses has made a big difference. These new varieties and mixes are better suited for high-producing dairies. They are more productive, palatable and keep cows healthier while still producing.
“Cattle were designed to eat grass, and today we have higher-yielding grasses that can take manure application much better than other crops,” says Wilson. Every dairy needs a place to go with manure, and grass is the ideal crop to utilize it and maximize growth. A grass stand can often last five to 10 years and keep producing high yields and is more cost-effective than crops requiring faster rotations or annual planting.
“One of the grasses in the mix we use is a soft-leaf tall fescue. It is very durable and palatable, has better digestibility and is better utilized by the animal,” he explains.
Wilson’s company has focused on improved grasses for more than 115 years. “In the crop world, there are many improved options to choose from, and there has been a lot of research on grass as well. When selecting a grass or grass mix, you want to make sure it is an improved variety that will keep a dairy cow producing at her peak,” says Wilson. There are certain mixes that might fit better for certain dairies, as well.
Grasses are a small part in the whole feed system for these dairies, but are very beneficial. “With research and development of new improved forage grasses, they have helped change the game, bringing grasses to another level that enable them to be used on high-producing dairy farms,” Wilson says. The most important thing is keeping the cows healthy and happy, and having some fresh high-quality grass in the feed mix seems to do just that.
Daryl Woldt near Brillion, Wisconsin, runs a large dairy milking 1,425 cows and raising 1,000 heifers and has been using grass in the ration for 10 years, harvesting it conventionally and putting it in bags or piles. He started this new green feed program on May 17, 2020, and it has worked very well. “We started with a few pounds of dry matter per cow per day and worked up to nearly 7 pounds of dry matter per cow per day. This is a fairly large volume of grass, since green grass is mostly water. For our herd, it takes a semi-load per day,” he explains.
The farm has about 4,500 acres in crops and had already planted some of those acres to high-producing grasses. “We used a combination of tall fescue, meadow fescue and festulolium,” says Woldt. Some of these fields also have a little red clover. This combination makes a very nutritious and palatable forage.
“We found it helped the cows’ intake and we were able to back off on the protein and starch in the rest of the ration.” This resulted in considerable savings in purchased feed cost, and cows were getting more of what they needed from the fresh grass.
“The fiber is more digestible than in most grasses, and you’re getting the enzymes and other things the cow needs – making a healthier diet. The cows are getting more fiber instead of grains, which is better for the rumen,” he explains.
“We have quite a few acres of grass, so if it got dry during the summer we were able to go to different fields. If we had 250 acres, we were greenchopping and it stopped raining and that field was dry, we were able to go to some other fields and continue greenchopping. We were still greenchopping in late October and figured on doing it several weeks longer, until snow,” says Woldt.
“We hoped to get six months of greenchop – and may be able to start even sooner next year if we leave more regrowth on some of the fields this fall so the grass will start growing sooner,” he says.
“When we’re greenchopping, averaging about 10 acres per day, depending on how much rain we get and how fast it is growing, we can haul up to 10 semi-loads of manure each day. We apply approximately one load per acre (5,000 to 6,000 gallons). We put manure back on the field right after we harvest the grass, though we sometimes wait three days or four and then cover the entire 30 or 40 acres at one time.” This makes a perfect cycle for fertilizing and re-growing the grass. Grass really likes manure and does very well, so the cows are helping grow their own feed in a perfect balance.
“When it’s raining or there’s heavy dew in the morning, if we have to greenchop early, we adjust the dry matter of the feed going into the TMR, adjusting for the extra moisture. If there’s no dew or rain on it, the grass runs around 80 to 82 percent moisture, but if it’s wet with rain or heavy dew it can be as high as 88 percent moisture. We just adjust the TMR to accommodate that difference,” he explains.
“This system works well and has been worth it. With that feed going directly to the cows daily, we don’t have to put it in a pile or pack it or cover it. There is no shrink, and you don’t have to face it and get it off the pile, so this saves time and labor as well.”
“I wish I could milk 5,000 cows during summer and feed them this way, and not have to milk any in the winter. When you add up the savings on feed costs, shrink and storage, it made a big difference. We were able to drop our protein in the ration from 17 to 16 percent and drop the starch from 27 or 28 percent down to 23 percent, so these were expenses we were able to take out of the ration,” says Woldt.
“We harvest the feed with a 20-foot direct-cut head mounted in front of one of our self-propelled forage harvesters and pull a dump cart behind the forage harvester, which makes it a one-man operation.”
Eric Staudinger, the dairy nutritionist who works with Woldt Farms, says they capitalized on the equipment they already had. “There is some cost of harvesting each day but no storage loss from harvesting and fermentation or ensiling cost. The fiber digestibility of that young grass is very high. We were able to increase the forage percent of the ration and decrease purchased feed,” says Staudinger.
“We increased forage in the diet about 8 percent at one point and decreased purchased feed costs by about 70 cents per cow, and the cows liked it. We looked at the diet in terms of fiber digestibility per pound, and it’s probably as good or better than the fiber in corn silage. The amount fed is controlled; we started out slowly with a lower feeding rate and increased it a little every week or 10 days. We kept increasing it and decreasing our other nutrients until the cows told us it was optimal,” he says.
Grass makes a good crop on many dairy farms because it is heartier than other crops and doesn’t have to be replanted as often. The system works well, and it was eye-opening to see the savings in feed costs.
