Nurse-crop selection always involves trade-offs.
If you don't use the right nurse-crop prescription this spring, your new alfalfa stand may need a little doctoring.
Pick the right mix for your climate, production practices and market, advises Dan Undersander, University of Wisconsin forage agronomist.
Undersander, who has worked extensively with alfalfa nurse crops ranging from peas to small grains like oats and triticale, sees trade-offs with each one.
“It's up to the grower to know which one works best for him,” the agronomist says. “He needs to think about what he's going to feed it to.”
The wrong nurse crop may outcompete and weaken a new alfalfa stand and/or reduce the overall value of your first year's production.
And none of the big three nurse crops — peas, oats and triticale — offer the ideal solution for every grower, Undersander believes.
“Peas are a good high-quality forage, very sweet and something cattle really love. But if you have any kind of a storm, they don't stand up well,” he says.
“Oats, on the other hand, are hardy and grow well, but lack palatability.”
He adds that the new beardless triticale is palatable and tough, but has a tendency to out-compete alfalfa. The popular rye-wheat cross has been known to bolt 3" in 24 hours.
Blends are often a good solution. Mixing peas and oats is popular in the Midwest, Undersander says.
“Dairy people like it because it's more palatable than straight oats but it stands up better than straight peas.” It's usually ensiled, he adds.
Blended peas and oats yield about the same as straight peas or straight oats, Undersander says.
“When you combine oats with peas, you don't change the tonnage. You only change the palatability of the forage.”
Undersander recommends a 50-50 oats-peas blend; he usually seeds 50-100 lbs of it with 15 lbs of alfalfa.
The cost of the blend is about $9/acre higher than that of straight oats. But it's worth it if fed to milk cows, Undersander adds.
“But if you're feeding heifers or beef cattle, you would probably go with straight oats,” he says.
At Quincy, WA, dairy hay producer Tom Downs uses a peas-only nurse crop. An oat-pea blend doesn't pass muster with most dairy operations in the Northwest, he says.
“A little bit of oat hay goes a long way,” adds Downs, who grew oat hay before switching to Austrian peas. “You're lucky to get $65/ton.”
In a region where severe summer storms are a rarity, Downs is pleased with the performance and economics of a peas-only nurse crop.
“In addition to the soil conservation benefits, I can get an extra 11½ tons of product that is comparable to pure high-protein alfalfa,” he says.
Downs produces high-quality dairy hay that currently sells for $105/ton. He can gross $150/acre more by producing and selling pea hay than by selling the same cutting without a nurse crop.
“The dairymen are ready to pay the same price for the pea hay as they do for the straight alfalfa,” he says. “And on that first cutting with the peas, you get the same yields you would get with an established alfalfa field.”
Calculating the cost of peas at 15¢/lb and labor/equipment costs at $10/acre for seeding, Downs nets $135/acre more when he plants a pea nurse crop.
But to make that kind of money, growers need to recognize when to take the first cutting, Undersander says.
“If you cut too late, your nurse crop will out-compete your alfalfa and it will reduce your first year of production, If you cut too soon you'll lose yield on your first cutting.”
Traditionally, the first cutting on a new alfalfa stand is 60 days after emergence. In that situation, peas should be between the flowering and early pod stage while oats, depending on the variety, should be at the early dough stage.