As forage stands age, plant species composition shifts and production declines over time.
There are many different methods of rejuvenating or renovating forage stands and strategies vary in intensity, effectiveness, and cost.
Breaking old stands and reseeding forages, while effective, is among the most expensive rejuvenation methods. So more producers are opting to improve their older tame pastures and reseed legumes using a key resource they already have on hand — their cattle herd.
At Nerbas Brothers Angus, they take a “hooves not harrows” approach to improving older pastures.
“We just try and use grazing as much as possible to take the mechanical component out of it,” said Arron Nerbas, who operates on his family’s multi-generational farm near Russell, Man.
The purebred and commercial Angus cow-calf operation has no cover crops or annual species and relies solely on perennial forages. Their goal is to try and graze as long as they can each season, and minimize the number of months they have cattle on winter feed, which is typically provided through bale grazing.
Nerbas said they plan out their grazing, moving cattle every two to five days.
“Anything that we graze by about June 15 or earlier, we won’t graze for the rest of the (growing) season,” he said, adding they will return to those fields again and graze them after freeze-up in the fall or the following spring.
Saving forage to use in the winter as stockpiled grazing is a significant part of their management strategy but he admits that their main goal hasn’t been reseeding.
“Using stockpiled forage has its own benefits due to efficiency in feeding, but (reseeding legumes) is definitely a side benefit,” Nerbas said. “We haven’t renovated a forage stand in 10 years or more.
“Going forward our plan is to probably never rip up and renovate the traditional way.”
They work with different land types on their farm and different species composition within that, but Nerbas believes that grazing stockpiled forage can work to reseed almost any species. “Anything that hits maturity that has viable seeds in the seed head that gets smashed or trampled into the ground will become some new seedling,” he said.
They’ve seen increases in legumes in particular.
“When cattle are grazing mature alfalfa, they trample and shake all those seeds down. You’ll see it in grasses too like meadow brome and other brome grasses. If you leave residue there, they trample quite a bit in. Over the years we’ve seen soil improve and forage production improve.”
They examine the manure to look for forage seeds that pass through the animal’s digestive system and also use that as an in-the-field estimate of whether their herd is getting enough quality forage when they are grazing stockpiled pastures.
Nerbas has tried other experimental methods of seeding legumes including broadcast seeding using an airplane, which has shown a lot of promise. They’ve also tried mixing seed in loose mineral although they have had mixed results with this approach.
“It’s extremely patchy. The seeds accumulate in small little clusters,” he said.
Managing rotational grazing and using stockpiled forages has enabled the Nerbas family to get more days of grazing every year out of the same land base, all while rejuvenating older forage crops.
“That’s a key indicator that the land is healthier and forage production is increasing,” Nerbas said. “The goal is just to try and improve the land over time.”
There are a number of resources at beefresearch.ca including a webinar titled ‘Assessing winterkill and what you can do about it: Forage rejuvenation’ and ‘Let Cattle do the Seeding’.