Source: Alberta Agriculture and Forestry
Annual forages are a flexible alternative for producers who feel they may be short of pasture forage or want to improve land soil health.
“By seeding annual pastures, producers can give stressed perennial pastures a rest,” explains Karin Lindquist, forage and beef specialist at the Alberta Ag-Info Centre.
“If those pastures are rested early in the spring and following rain, they can produce good amounts of growth later in the summer. However, if used early in the spring, those stressed pastures will be a huge disappointment this grazing year.”
Annual forages can also be used for high quality silage or greenfeed to add to next winter’s feed supply.
She says that seeding annuals needs to be done as early as possible if the goal is to graze the field. They need about 6 weeks to grow before they are ready to graze.
“We advise producers to hold off grazing annual cereals until the seed rows have filled in to ensure the plants are well established. Barley or oats will give the fastest growth and the earliest grazing readiness. Winter cereals are slower to establish for grazing, but they have the benefit of growing more uniformly all summer and fall.”
She adds that winter cereals may even be used next spring in some areas, depending on grazing management and over-wintering conditions.
“You can add to this mix or replace the winter cereal with some of the other annuals offered – forage rape, annual legumes, warm-season grasses, turnips and radishes – for later or even fall-winter season use for silage or grazing in dry conditions.”
“Seeding a mixture of spring and winter cereals may work the best as they are often easy to find,” she explains. “A properly balanced seeding mixture of spring and winter cereals for grazing can increase dry matter yield. It’s the same case with other annuals in place of winter cereals.”
With each year’s growing conditions varying from the last, having a diverse forage mix ensures a more stable yield, but only if the forage mix is properly balanced to grow what’s desired.
Lindquist says that most forage seed companies now carry these diverse annuals but booking early is the key to getting what will work best for your particular goals.
“Talk to them and ask for information so you can make the correct mix decisions for your purposes.”
If a producer is seeding a spring-winter cereal mixture for grazing, she recommends that the seeding rate is about 150% of a normal stand.
“In a 1:1 spring-winter cereal mix, seed three-quarters normal seeding rate of the spring cereal and three-quarters normal seeding rate of the winter cereal. Alter the mix accordingly to promote earlier or later forage growth. The same principle would follow with the diverse annuals or cocktail mixes.”
She says to keep the brassicas low enough that nitrate issues or too-high sulphur levels are not an issue. Italian ryegrass needs more moisture than winter cereals, so it will not work as well in drier areas.
Consider soil test results, moisture potential and projected yields when planning fertilizer application. Fertilizing after each grazing will increase yield. Grazing rotationally allows rest and recovery time for the plants, which will lead to higher yields in annual pastures.
Lindquist mentions that it is important to supplement livestock with a high calcium mineral that contains magnesium when grazing cereals, especially as the pasture matures.
“Magnesium is not highly palatable, so its consumption needs to be carefully monitored. We suggest starting the animals on the mineral at least 1 week before going out to graze. That way, the animals have adequate levels of magnesium in their system to prevent tetany, which can be triggered by the lush vegetative growth.”
“Calcium deficiency can be an issue with cattle herds grazing cereal forages and when grain is fed,” she explains. “The brassicas and annual legumes address the need for a high quality forage that has higher calcium levels. Cereal feedstuffs tend to be higher in phosphorus, so the calcium-phosphorus ratio is thrown out of balance. Calcium and magnesium supplementation is crucial.”
She adds that if a cow herd only eats a cereal-based forage diet during summer or winter-feeding, they will need a balanced mineral supplementation for rebreeding and to prevent grass or winter tetany.
“A balanced trace mineral supplementation is important if brassicas are being fed to offset potential high sulphur levels.”
Connect with the Alberta Ag-Info Centre:
Hours: 8 am to 5 pm (open Monday to Friday, closed statutory holidays)
Phone: 310-FARM (3276)
For media inquiries about this article, call Alberta Agriculture and Forestry’s media line: