Suitable grass species and varieties can offer significant advantages when included in alfalfa-grass mixtures for dairy cows and milking goats as haylage, baleage or dry hay. These advantages include nutritional improvements in fibre digestibility, increased intake and higher milk production, as well as agronomic and harvest advantages.
There is currently a great deal of interest by dairy producers to include newer grasses in alfalfa-grass mixtures, and a move away from the use of alfalfa-timothy. Quality Seeds has selected late-maturing grass varieties that improve forage quality at first-cut with later heading, with more vegetative regrowth in subsequent cuts. Improved Quality Seeds varieties of highly digestible meadow fescue (Tetrax, Raskila), soft-leaf tall fescue (Elodie, Dauphine), very late-maturing orchardgrass (Diceros), festulolium (Lofa), and perennial ryegrass (Valerio) offer significant benefits.
1. Agronomic Advantages
Alfalfa-grass mixtures typically yield higher than straight alfalfa stands, in all cuttings. In Ontario trials, yield increases of 15 - 20% are typically observed. Nitrogen fixed by the alfalfa is used by the grasses to meet their high nitrogen requirements. Grasses have much less issues with persistence and are more tolerant to variable drainage, low potassium fertility, disease and winterkill. Grasses in mixed stands provide some protection against lodging, and are also better able to compete with weeds.
2. Harvest & Storage Advantages
Grasses in mixed alfalfa stands enable faster wilting and drying, resulting in reduced respiration losses of non-fibre carbohydrates. Because alfalfa tends to buffer itself during haylage fermentation with a slower drop in pH, grasses can also improve fermentation, particularly in baleage situations.
3. Dairy Cow Nutrition Advantages
Grasses tend to lose forage quality faster than alfalfa after the heading stage, so it is critical that cutting schedules be timely. Unlike in the past when first-cut was started in mid-June and it was followed by one or two cuts, most dairy producers today begin in late-May and aim to cut every 4 weeks. Grass mixtures can work very well with current cutting schedules. Early-cut grasses are very palatable and can complement alfalfa nutritionally.
Grasses are higher in fibre (NDF) than alfalfa, but are also much higher in fibre digestibility (NDFD). Refer to Table 1 – Fibre (NDF) & Fibre Digestibility (NDFD) Levels of Alfalfa & Grass. Although there is a wide range, grasses may have 12 – 13 % points higher NDF than alfalfa, but grasses also have at least 12 – 13% points higher NDFD or more. Grasses contain much more hemicellulose than alfalfa, which is the highly digestible component of forage fibre.
Higher fibre digestibility has two benefits – higher digestible energy per unit of feed as well as higher cow intake, resulting in more milk per cow. This is especially the case where intake is limiting production – transition, fresh and high producing cows. A much quoted study by Oba & Allen, MI State 1999 concluded that for every 1 percentage point increase in NDFD, intake increases 0.37 lbs/day and milk increases 0.55 lbs milk/day. Dr Jerry Cherney, Cornell University, has stated “Feeding trials across the USA have shown that a one percentage unit increase in NDFD increases milk production by 0.5 to 1.0 lbs/cow/day, and more than 1.0 lb/cow/day for the highest producing cows”. Grasses in early cut alfalfa-grass mixtures can complement the alfalfa by improving fibre digestibility. Even small percentages of grass in an alfalfa-grass mix can provide significant improvements in NDFD. Alfalfa-grass mixtures with 25% grass can significantly improve NDFD by over 3 percentage points over straight alfalfa.
Table 1 – Fibre (NDF) & Fibre Digestibility (NDFD) Levels of Alfalfa & Grass
(Source – Dairy Forage Lab, Ithica, NY and Miner Institute)
When nitrogen is not limiting, grasses have moderately high crude protein levels, but not as high as alfalfa. Alfalfa often has very high crude protein (CP) levels, but the CP is very soluble, limiting its efficient utilization by the cow. Mixed alfalfa-grass stands can have high CP content with better protein utilization.
Rumen Dynamics
Alfalfa and grasses can complement each other in a dairy ration. As discussed previously, grasses have higher fibre (NDF) levels (~12% points) than alfalfa, but they also have greater fibre digestibility (NDFD) (~12% points, 30 hours). Grasses also have much lower levels of undigestible fibre (uNDFD240) that limit intake. While alfalfa fibre has an initial faster rate of digestion, it then slows down. Grasses have a greater extent of digestion. This results in higher animal intake.
The fibre particles in grasses are less fragile in the rumen than in alfalfa with more longer particles, so the particle size decreases less rapidly. This improves the physically effective fibre (peNDF) in the rumen. This decreases the need to add straw to a TMR to provide minimum physically effective fibre for proper rumen function and cow health, while contributing much more digestible energy than straw.
How Much Grass Is Optimum?
Variability of grass percentage in alfalfa mixtures is a potential issue because it can result in variable quality forage. Keep in mind that % grass in a seed mixture is not the same as % grass in the subsequent forage stand. Some grass species are more aggressive than others, and small seed amounts (as low as 3%) can result in significantly more growth. Percent grass also changes over time and is strongly influenced by environmental conditions such as rainfall during and after establishment, and cool spring temperatures.
Early Cornell University research suggests that the optimum grass in alfalfa-grass mixtures at the end of the seeding year may be around 5 – 15% grass, with about 20 – 30% in the first full production year. Cornell University and some laboratories have developed NIRS calibration equations to estimate grass percentages in alfalfa-grass samples. (Alfalfa- Grass Mixture – 2016 Update http://blogs.cornell.edu/whatscroppingup/2016/12/02/alfalfa-grass-mixtures-2016-update/)
To prevent against excessive grass percentage in alfalfa-grass stands, too much grass when it occurs can be managed by:
1. selecting an aggressive alfalfa variety,
2. selecting the appropriate grass species and varieties,
3. using the correct grass seeding rate,
4. avoiding excessive liquid manure (nitrogen) application, and
5. lowering the cutting height from 3-4 inches to about 2 inches for a cut or two.
Timothy
Historically, timothy has been the main grass species used in alfalfa-grass mixtures. However, there has been a move away from timothy as many dairy producers have looked for species that are more productive agronomically, as well as providing higher feed quality in the ration. “Old school” advantages of timothy include:
late heading dates are more suitable to late first-cutting (June),
it is less competitive with alfalfa,
the seed is small and mixes well with alfalfa to go through the drill small seed box, and
the seed is relatively inexpensive.
The weakness of timothy is that it is shallow-rooted with very poor drought tolerance. It is also daylight sensitive which makes it want to grow in the spring but not after late-June with decreasing day-lengths. This results in lots of timothy growth in the first-cut, but very little regrowth, making it a “first-cut wonder” with poor seasonal growth distribution. Alfalfa-timothy mixtures are inconsistent across cuttings, having a high percentage of timothy in the first-cut while subsequent cuts are almost straight alfalfa. Quality Seeds offers more modern, improved grass species, such as meadow fescue, tall fescue, and orchardgrass) that have much higher seasonal yield by providing increased vegetative regrowth in 2nd, 3rd and 4th cuttings. Also, timothy is not very tolerant to frequent, aggressive dairy haylage cutting schedules, and does not perform or persist as well in these systems.
Improved Grass Species & Varieties
Quality Seeds has introduced the “M.D.” Maximum Digestibility designation on our most digestible grass varieties. Grass varieties that are marked M.D. are significantly higher in fibre digestibility (NDFD) than other varieties of the same species. These grasses offer maximum fibre digestibility and increased intakes to help promote higher milk production and beef gains.
1. “Tetrax”and Raskila” Meadow Fescues
Meadow fescue has recently been rediscovered as an excellent grass to include in dairy haylage alfalfa-grass mixtures. Quality Seeds plot data and research by Cornell University and Miner Institute shows much opportunity with alfalfa-meadow fescue mixtures. Meadow fescue has higher fibre digestibility and forage quality than most other grass species. Meadow fescue is less competitive with alfalfa, which can be an advantage in alfalfa-grass mixtures where a modest grass content is more desirable. It has a soft texture and is very high in palatability.
Meadow fescues have excellent winterhardiness. Drying rate is much faster than ryegrass or festuloliums. Small amounts of meadow fescue seed can be included in alfalfa mixtures and still flow through a drill small seed box.
“Tetrax” is a next generation, very recently introduced meadow fescue. It is the first and only tetraploid meadow fescue introduced to the Canadian market, and is exclusive to Quality Seeds. It is an extremely soft leaved variety with superior digestibility and palatability. It is also very persistent. Tetrax is a M.D. Maximum Digestibility designated variety.
““Raskila” meadow fescue is a leafy, high yielding diploid variety exclusive to Quality Seeds. Raskila is noted for very soft leaves and extremely high fibre digestibility, with strong disease resistance and persistence .
2. “Elodie” & “Dauphine” Tall Fescues
These newly developed soft leaf tall fescues are much improved in palatability and quality than the older tall fescue varieties, which tended to be coarser, sharp textured, less palatable, with lower forage quality. Soft-leaf tall fescues are much softer in texture, and provide a big improvement in palatability and intake. They are very high in fibre digestibility. Soft-leaf tall fescues have excellent agronomics and are high yielding compared to other forage grass species. Tall fescues are deep rooted and very drought tolerant, and can provide significant vegetative growth during hot, dry summer weather.
Soft-leaf tall fescues wilt and dry quickly so it is suitable for haylage, baleage or dry hay. Of course, Elodie and Dauphine are endophyte-free varieties. Experience has shown that modest amounts of tall fescue seed can be included in alfalfa mixtures and still flow through a drill small seed box and provide significant growth.
Elodie and Dauphine are the newest generation of extremely soft-leaf tall fescues. They have superior palatability and digestibility compared to older varieties, along with outstanding drought tolerance and persistence, with excellent regrowth. Elodie and Dauphine are both M.D. Maximum Digestibility designated varieties.
3. “Diceros” Orchardgrass
Diceros is an exclusive Quality Seeds orchardgrass variety that works exceptionally well in alfalfa-grass mixtures. Older orchardgrass varieties have a reputation of early maturity (early May) and poor forage quality, but this has dramatically changed with the introduction of these newer very late maturing varieties. They have much later heading dates than other orchardgrass varieties (more than 3 weeks later than early varieties) and a similar heading date to late-maturing timothy varieties. Research also shows that these varieties are slower than other orchardgrass varieties to decline in digestibility and palatability after heading, providing a much a wider harvest window. Diceros is extremely late heading and is a M.D. Maximum Digestibility designated variety.
Diceros has become a staple in many of Quality Seeds alfalfa-grass mixtures with high yields, excellent forage quality and high fibre digestibility. They are leafy, fine textured and very palatable, and also provide high yields of vegetative regrowth in subsequent cuts. They wilt and dry quickly so are suitable for haylage, baleage or dry hay. Diceros seed is coated so that when mixed with alfalfa and other grass seed at 3 to 5%, it will flow through a drill small seed box.
4. “Lofa” Festulolium
Festuloliums are crosses between ryegrass and either meadow or tall fescue. They have been selected to have the forage quality and fast growth of the ryegrass combined with the persistence of the fescue.
Quality Seeds Lofa festulolium has inherited high forage quality from its Italian ryegrass parent, but with improved yield, growth during hot dry summer weather, and persistence from its tall fescue parent. It is noted for being very high in sugar content and digestible energy. A strong root system allows it to be more productive in dry summer weather than ryegrass. It is best suited to aggressive cutting schedules in dairy haylage systems.
Although it will head out every 28 days or earlier, feed analysis data shows that Lofa maintains its nutrient quality advantage after heading very well. It can be competitive with alfalfa in mixtures so percentage inclusion should be modest. Festuloliums can sometimes be difficult to dry for hay, so they work better when harvested as haylage or baleage.
5. “Valerio” Perennial Ryegrass
Valerio is a newer perennial ryegrass that is extremely productive in cool and damp climates. It is high yielding under these conditions with good cold tolerance and disease resistance. Valerio has exceptionally high nutritional feed value, with very high sugar content, fibre digestibility, digestible energy and palatability. Valerio has much improved persistence compared to other perennial ryegrass varieties. Perennial ryegrass can be more difficult to dry, so haylage or baleage is a more suitable harvest option than dry hay.
Suggested QS Alfalfa-Grass Seed Mixtures
Quality Seeds alfalfa-grass mixtures that are currently being offered to dairy producers to make high quality haylage include:
· 90% Quality Seeds alfalfa
· 5% Dauphine tall fescue
· 5% Tetrax meadow fescue
· 89% Quality Seeds alfalfa
4% Dauphine tall fescue
4% Tetrax meadow fescue
3% Diceros orchardgrass
· 92% Quality Seeds alfalfa
8% Tetrax meadow fescue
These mixtures provide high forage quality as well as increased yields. They have the additional benefit that the seed mixtures will flow through the small seed box on most drills. Talk to your Quality Seeds representative to choose the alfalfa variety and grass mixture best suited to your farm and management.
Pure Grass Stands
These grass species and varieties can also have excellent performance when grown in pure grass stand mixtures when managed appropriately. Quality Seeds offers the grass mixture “Milk Max”, suitable for dairy haylage and baleage, consisting of 25% Diceros orchardgrass, 25% Dauphine tall fescue, 25% Tetrax meadow fescue and 25% Valerio perennial ryegrass.
The newly introduced “HayMax” mix which can be dried for dry hay, consists of 45% Raskila meadow fescue, 40% Dauphine tall fescue and 15% Diceros orchardgrass.
Fertilizing each grass cut with nitrogen is important for yield and quality. Regrowth is faster and more vigorous when cutting height is 4 inches.
Quality Seeds Grass Variety Research
Quality Seeds has positioned itself to be the Canadian leader in improved grass species and varieties. Searching around the world for new potential “game changer” grass and alfalfa varieties, they are tested in Canadian environments to research how they perform for yield, quality and persistence in our soils and climates. Quality Seeds has been a leader in innovation by introducing new specialty trait grasses, such as the highly digestible tetraploid Tetrax meadow fescue, the extremely soft-leaf Dauphine tall fescue, and the late-maturing Diceros orchardgrass, as well as the extremely highly digestible Evolution Italian ryegrass. New Quality Seeds varieties of the next generation of highly digestible grasses will continue to be introduced.
