In some circles, it is always a struggle between yield and quality when it comes to forage production. Well, which one is more important? Here at Forage Innovations (FI), we have a difficult time choosing ourselves! Obviously, you cannot be effective with a high-forage diet (and this is always our goal) if the quality (read—digestibility) is lacking. And at the same time, you cannot feed a high-forage diet if forage inventory is lacking, either.
Increasing the quality of a forage is limited to a relatively small number of things. Of course, the particular cultivar and all those attention-to-detail things are important to increasing yield. But the most important quality determiner by far is the seed or plant. With which you begin. All the other management strategies are mainly attempting to harvest and preserve the quality we had to start. Somebody said there are (only!) 1000 variables when growing a crop (and probably 900 of those pertain to the weather!).
So, Can You Increase the Yield?
How do we increase yield? Researchers and seed companies test cultivars for yield constantly. This attention to identifying the best cultivars is important and separates the winners from the also-rans.
However, one of the easiest ways to get more yield when all else is equal is by using polycultures. Graziers have used these methods for years. Gabe Brown, a widely known and highly successful beef grazier is the current guru. He seems to throw everything except the kitchen sink into his pasture seedings with great results. At FI we have adopted some of these recommendations but have become a bit more intentional when we are recommending seed mixes for dairy and aiming for high-forage diets, and high milk production.
Figure 1 shows plots on Daniel’s farm where various mixes, fertilizations like nitrogen/sulfur levels and various crops work or do not work together. Often legumes are planted in one direction, say East to West and grasses are planted North and South with replications. These plots allow us to see how particular crops work when sharing their rhizosphere. Do they gain from this sharing, or does it hinder? This is knowledge that almost no one in the seed industry from research techs to sales managers has other than Daniel Olson! When it comes to alfalfa, alfalfa breeders and sales directors despised what we were doing and only now grudgingly accept it. You will see why below.
Some of the color differences you see are from fertilizer trials plus some grasses are a lighter green. In the spring of 2023, Daniel attempted to establish his largest trial yet, but droughty weather may have caused a replant. We will know for sure in a couple more months!
Improving the Yield of Alfalfa
Alfalfa was one of the first crops we tried this idea way back (yes, around the turn of the century!). Alfalfa is the dairy forage crop that needs the most help when it comes to yield. Modern GMO alfalfas with slightly higher digestibility usually produce lower yield. They do not reach our goal of higher digestibility and higher yield. Ernest Weaver, a long-time seedsman, and experimenter at Byron Seeds, LLC promoted mixing alfalfas even though we did not know why it increased yield, but it did!
Olson then took eight different alfalfas planted both separately and then as a mixture of all eight. The mixture produced 30% more than the average of the individual varieties and 19% more than the highest yielder of the eight! We were advised by Dr. Dan Undersander, UW-Madison Agronomy Professor-Emeritus, when refining our selection, to look at combining alfalfas from different breeding programs and with different root systems. Now you see why no alfalfa breeder wants to promote his best alfalfa blended with some other companies great alfalfa! This was the start of the KingFisher Synergyx Alfalfa program.
The principle for alfalfas is to mix great alfalfas (with the best digestibility, but different root systems) to get one which will yield more. Of course, we look for disease packages and yield of the alfalfa when planted alone.
After looking at alfalfa, two other mixing steps naturally follow. Mix some 4-year Red Clover (a rare find, but we have one!) into the mix. This helps both digestibility and protein quality since on the average red clover is nine percentage units higher than alfalfa and has twice as much rumen undegradable protein (RUP or bypass).
In fields that are not uniform (you mean everybody’s hayfields are not perfectly level?), adding Red Clover to an alfalfa seeding can really improve yield. You will think only the clover was sown in those areas where alfalfa typically has not done well. And of course, by having a productive quality plant growing in these normally barren (or full of weeds) areas increases yield and quality.
The last step is adding grass to the mix! Modern-European Genetic late-heading grasses such as Meadow Fescue (for Upper Midwest) increase both yield and quality. These cool season grasses are the common forage with the highest digestibility. Often, dairy managers learn the value of high-quality, late-heading grasses where they have thickened up an alfalfa stand by seeding in either an Italian Ryegrass or festuloliums into the stand to keep it going another year or two.
Our cocktail mixes are typically a mixture of BMR sorghum-sudan (SxS), Italian Ryegrass and annual red clovers. Obviously at FI, the first step is starting with very digestible varieties. Then we look for ones which will co-exist well with the other “team members” for yield. Our cocktail mixes feature a mixture of warm season and cool season grasses. This gives the added benefit of being able to thrive in either dry hot or cool wet years and be an insurance policy for forage in either extreme. In normal(?) years everything goes well. In addition, we virtually always follow the cocktail sorghum with corn for silage. The root exudates of the sorghum in the cocktail mix provide an ideal start for the corn both as a natural insecticide and herbicide. Your first-year corn will be even better.
What about Cool Season Grasses
It has long been a strategy for grass seed companies, of mixing diploidal and tetraploidal types of ryegrasses to gain from each ploidy’s strengths. The terms diploid and tetraploid denote how many sets of chromosomes exist in each cell. Each ploidy, in general, has different strengths. These intentional mixtures of the best of both improve the resulting grasses.
We have also commonly blended varieties of cool season grasses to gain from each varieties strengths, both with the same and different varieties.
Take Home Message
Quality is limited by the variety and species, but yield can be increased by blending several varieties and/or species which have shown in our above-mentioned plots to work in a synergistic fashion. The results of this approach can be dynamic in increasing a farm’s performance and decreasing ration costs.