Silvopasture Has Multiple Benefits By Greg Brann
ADOLPHUS, Kentucky:
Silvopasture has definitely been gaining a lot of attention lately, and for good reason. Allan Nation referred to it as a holon, a whole system in and of itself, but it’s also a part of the larger system.If you already have the land and are managing grass, cattle, and even small ruminants, adding trees is the next natural step. It’s basically stacking enterprises on the same land. Silvopasture can involve adding trees to pasture or thinning a woodland to allow for grass growth.
ADDING TREES TO PASTURE
Silvopasture yields 42 to 55% more product than grass, livestock, and timber grown separately. Research in Missouri found that providing shade for cows can have multiple benefits. Cattle grazing on endophyte-infected tall fescue with shade gained an average of 0.72 pounds more per day compared to cattle without shade. Additionally, the presence of shade helps moderate moisture and temperatures, leading to longer soil life activity. Providing shade also results in lower water consumption by livestock due to the lower heat humidity index.
Shade has been found to improve cattle performance significantly. An Arkansas study showed that cattle with artificial shade had an average daily gain of more than 20% compared to those with no shade, and those with tree shade showed nearly a 60% increase. In Virginia, a study by Dr. John Fike demonstrated that stress levels (cortisol) in sheep are lower in areas with black walnut and thornless honey locust compared to open pastures. Additionally, a Missouri study found that cows on infected tall fescue with shade had a 50% higher calving percentage compared to those with no shade.
PLANNING YOUR SILVOPASTURE
When choosing the tree size to order, research has shown that younger trees catch up with older transplants within two to three years. Smaller trees have fewer disturbed roots, so they are able to establish more quickly than older, taller transplants. I like trees that are two to four feet tall. If the seed- lings you purchase are less than two feet tall, you can plant them in the garden for a year and then transplant them to the field.
Larger trees cost more, and due to the amount of roots removed when dug, they are often slow to take root and grow. Larger trees are also prone to more shock and require more protection against being wind-blown until the roots are well established. Some examples of trees that are often used in silvo- pasture are walnuts, black locusts, thornless honey locusts, pecan, persimmon, oaks, and chestnuts. I use sumac groves to provide shade in some pastures. Typically, it takes five years for trees to reach 15 feet or taller, but it varies between species, soil type, moisture, and other factors.
A mature stand of 40 feet diameter canopy trees in silvopasture is only seven trees per acre. Trees can be planted in a linear pattern or more of a savannah planting, randomly distributed throughout the pasture. It doesn’t take many trees to give the benefits you’re looking for.
The first five years of management are the most crucial. Tree protection is paramount. Typically, you will spend about twice as much on tree protection and staking as you do on tree seedlings. Trees need protection from livestock until they are at least fifteen feet tall. Livestock will walk trees down, browsing the leaves as they push them over. This is especially a problem with horned livestock.
A linear planting is easier to protect and manage, but a savannah planting looks more natural. When planting in a savannah-type setting, a six-foot or larger diameter hoop will protect trees the best. Some folks use reinforcing concrete wire or welded wire bull panels along with four steel posts to protect trees. Electric wire can also be used. In a linear planting, such as on an existing fence line, I plant trees 2.5 feet off the existing fence and add another single hot wire 2.5 feet away to keep cattle away from the tree. Sheep can graze under the wire, so I use a staked tree protector to reduce the impact of the sheep rubbing on the tree.
If your goal is to provide shade, plant trees on the South or West side of a field. Another option is to plant a block of trees that can be used from multiple fields. Although big, leafed trees provide a lot of shade, those big leaves can be slow to break down and shade out the grass on the ground, so smaller-leafed trees are generally preferred.
MAINTAINING YOUR SILVOPASTURE
As the tree grows, prune the bottom limbs before they are 1.5 inches and trim back to the growth collar so the cut will heal. When limbs are 4 inches or larger, it is best not to prune them because they are not likely to heal. I like to leave 30% - 50% or more of the height of the tree in leaf. Pruning limbs up to 21 feet will provide a very marketable log. Pruning bottom limbs also moves the shade away from the base of the tree, reducing the impact of compaction from livestock. Proper distribution of trees also reduces compaction because the livestock disperse more.
SILVOPASTURE FROM A FOREST
The other option for creating silvopasture is to remove trees from forested land. The woodland that is the best candidate for silvopasture is a mediocre woods.
Some issues foresters have with livestock in the woods are that livestock often browse young seedlings, not allowing the regeneration of trees. Livestock rubbing on trees,
as well as compaction from loafing around trees, which can cause manure stains in the wood, are other concerns. It’s good to be aware of these issues, but they shouldn’t be a deal breaker for silvopasture. Proper grazing management can minimize these concerns. Grazing woodlands is not silvopasture.
GROWING GRASS IN YOUR SILVOPASTURE
When creating silvopasture, growing grass for grazing livestock is what you’re after. Cool-season grasses need a minimum of 50% light getting to the ground, and warm-season grasses need a minimum of 60%. These are minimums; more would always be better. 65% light to the ground is best for optimum grass production. Forage production can be significantly reduced when available light is less than 35%.
Forages best adapted to low light are reed canarygrass, but it can be invasive, orchardgrass, Matua brome, Kentucky bluegrass, and tall fescue. Crimson clover is one of the best legumes for silvopasture, but annual lespedeza works well, followed by red and white clover. When it comes to native warm-season grasses, Eastern gamagrass, Virginia wild rye, and tick clover are the best. Forage grown under forest canopy had higher crude protein and greater in vitro organic matter digestibility than when grown in the open.
SUMMARY
Creating and managing silvopasture on your farm will enhance productivity and environmental ben- efits, improve animal comfort, and increase income. Choose tree species based on your goals, timeline, and your climate. Don’t overplant, and maintain enough light to the ground to grow grass. Protect and manage the trees, especially during the first five years. Plan for adapted grasses and legumes, reseed grass as needed, and rotate livestock a minimum of once per week. Install a water system that fits your needs, and always be observant.
Greg Brann is a consultant with the National Soil Health Division of NRCS and a private grazing consultant. He is a multi-species grazier in Adolphus, Kentucky. For resources from his 40 years of planning and consultations see www.gregbrann. com or Gregbrann.com for additional information.
