by Karl H. Kazaks
DRAKES BRANCH, VA — Kerwin Kunath has kept cattle and grown and managed timber all his life. It was only three years ago, however, that he decided to combine the two endeavors and start practicing silvopasture.
Kunath — who raises registered Charolais as well as commercial Charolais-Angus crosses and Cheviots — started with an 18 acre stand of loblolly pines near his home here in Charlotte County.
The trees were about 27 years old and had just been thinned from about 200 trees per acre to 60 trees per acre, with most of the trees taken for chip-n-saw and a few for pulpwood. The original plantation of 600 trees had been thinned to 200 trees at age 20, with most of the harvest at that time going to pulpwood and a few to chip-n-saw.
The understory was thick with briars, pokeberry, and hardwood saplings. Kunath envisioned it as a shady home for his livestock. So he hired someone to clear the brush and grind the stumps.
A few months later — in winter — he burned the stand. The following autumn he put down two tons of lime per acre and seeded oats, fescue, and ladino clover.
The oats were both to provide cover and erosion control and to permit spring grazing. The fescue and clover were for long-term grazing. Since then, the sheep and cattle (as well as a few horses) have enjoyed their new pasture.
The loblollies that remain standing are about 30 years old. When harvested, they will make good saw timber.
Practicing silvopasture requires careful management and planning. You have to be aware of the needs of your managed forest system, your livestock forage system, as well as the new hybrid ecology the two create when merged.
“We’re really just getting started with silvopasture in Virginia,” said Chris Teutsch, associate professor of forage and livestock at Virginia Tech’s Southern Piedmont AREC in Blackstone. “We’ve got lots of questions but not many answers.”
Silvopasture has one clear upside: the possibility of maximizing the production potential of a given site by producing two crops from the same piece of land. What’s more, the two crops provide different kinds of revenue: short-term cash flow from cattle and long-term high-value profit from timber.
Another postulated benefit of silvopasture is the ability of the system to provide cooler pasture climates for cattle. This can help both bred cattle enduring the heat of mid-Atlantic summers as well as cattle suffering from tall fescue toxicosis. One of the symptoms of that syndrome is elevated body temperature. Having a shady tree plantation in which to pasture your animals may be a way to mitigate cattle heat stress.
Cooler microclimates in silvopasture systems may also allow other forage species like orchard grass to be productive in those environments.
In the same way that grasses produce better when they’re not continuously stressed by cattle pressure during their growing periods, so too do trees benefit from having cattle rotate out of silvopasture areas.
According to Jason Fisher, forestry specialist for Virginia Extension’s Central District, you don’t want to run the risk of compacting the roots of your trees.
“The most productive roots for any tree species are going to be in the top four inches of the soil,” Fisher said. “That’s where the nutrients are.”
Farmers interested in silvopasture need to be aware of its acreage requirements: you need to have enough land to ensure both your cattle and your timber have the chance to grow healthily.
Kunath noted that in drier weather, grass around the base of the loblollies in his silvopasture will start to brown up, showing where the trees are using available water. In such conditions, your forage availability under trees will be reduced.
In his silvopasture system, Kunath includes both open pasture and pasture under trees. That — as well as having other available pasture — is partly how he manages the complicated needs of his silvopasture system.
When designing a silvopasture system, you have to take care not to let cattle in among trees that are too young. With loblollies, Fisher recommends not putting cattle in until the trees are at least 15 feet tall — about seven years.
“If they’re little bitty, cows can step on them, lean on them, run them over,” he said.
Then there’s the question of what tree species to use with silvopasture systems. It seems likely that most silvopasture in Virginia will be done with loblollies, due to their current use in plantations across southside and southeast Virginia, but there’s no reason the system properly adapted couldn’t work with other trees species as well.
Another unanswered question with silvopasture in the mid-Atlantic is the necessary minimum number of mature trees. Kunath’s has 60 loblollies per acre, but he thinks you could get away with just 50 per acre, letting in a little more sunlight and getting more forage growth.
But you can’t let a loblolly stand get too thin. Not enough trees per acre and the trees will be prone to ice and wind damage. What’s more, the loblolly crowns will grow too fast and the trees will bend and break the water column, damaging the trees and your investment.
Establishing silvopasture is an investment. It cost Kunath about $600 per acre to clean up his loblolly plantation — more than it would have cost to clean up a clearcut field, because the renovators had to work around his standing mature trees.
The investment in silvopasture is necessarily long-term, as even the shortest duration timber crops are measured in terms of decades. So interested farmers need to keep that in mind when deciding whether the system might work for them.
Whether it’s better to introduce silvopasture into mature tree plantations or into clearcut or clear pasture areas is a question Teutsch will be asking over the next several years, as part of a research project at the Blackstone AREC.
With the help of an NRCS Conservation Innovation Grant, the Research Center will be testing different ways of initiating silvopasture. One approach will be thinning trees and establishing grass in a mature plantation, as Kunath did on his farm.
Another will be to clearcut and then plant in a silvopasture configuration with wide alleys. With this plot the researchers may even test grazing newly established silvopasture by hanging a single hot wire to protect young saplings.
The research will test loblollies as well as hardwoods and also have a control area where a stand of loblollies will be converted to pure open pasture.
“There’s some real potential benefits for silvopasture in Virginia,” Teutsch said. “We don’t know all the answers, but you’ve got to start somewhere.”
Silvopasture may not be a trend yet in Virginia, but if it does become one, we’ll know where it started: on Kerwin Kunath’s farm.
In the meantime, Kunath is preparing to double the amount of silvopasture on his farm. This past year he cleared another 20 acres of 30-year old loblollies. By this time next year it will be seeded, ready for spring grazing.
Kerwin Kunath tests silvopasture in southside Virginia
by Karl H. Kazaks