Trees in silvopasture are not created equal John Fike for Progressive Forage Grower

For many producers, the thought selection soils or climate aren’t amenable to a orientation becomes an important of planting in is Tree selection is critical because, producer’s trees of interest. factor for optimizing light to the anathema. A common first utterance as one Virginia forester says, “You Combining different tree species forage understory, with north-south from skeptics generally goes can grow almost any tree almost may be a useful practice that can rows preferred at mid-to-higher something like, “My family’s been anywhere for a period of time – but not serve multiple functions. Planting latitudes, and east-west orientations fighting trees on this land since we necessarily well.” As much as possible, rows of conifers on either side of favored at low latitudes. However, came here, and now you say we should trees should complement the farm hardwood timber trees can provide a this must be balanced with other plant trees?” operation, not compete with it. Typical windbreak and simultaneously force considerations. For instance, layout Planting trees to create attributes for tree selection include the hardwoods to adapt a straighter must accommodate rotational silvopastures may not have the marketable timber, high-quality wood, and less spreading growth form, thus and appropriate feeder and waterer immediacy of thinning, but it can rapid growth, deep-rooted morphology reducing pruning. The conifers may placements, which are essential parts have several advantages. In contrast to to reduce competition with forages, be harvested for pulpwood, providing of good silvopasture management. And thinning, which typically is a take- open canopy to allow more light to much earlier returns to the system to avoid serious headaches, designs what-you-get proposition, planting the forage understory, early leaf-out than possible with hardwoods alone. also must account for future tree gives managers the opportunity to and late leaf-drop dates, drought Mixed plantings also may growth and leave room to move or select preferred tree species for any of tolerance, production of additional be useful where trees have turn around equipment in the field. several possible uses. products (e.g., nuts, , pine complementary or off-setting features. Planting also allows planning straw) and provision of environmental For example, black walnut trees Vegetation control for or adaptation to existing conservation services. Other have long rotation times and release Killing and removing existing infrastructure. This facilitates farm important criteria include cost, labor, compounds that are detrimental to vegetation typically are considered operations and provides opportunity site suitability, resources required for legumes. Thus, planting several black essential steps for tree establishment, to create desired interactions among establishment and management, and locusts between the walnut “leave” although this is somewhat species- trees, forages and livestock. the land’s tenure constraints. trees within rows could offset the dependent. Because no tree species will meet negative effects to clovers because For example, pines such as slash Planning for silvopastures all of these criteria, selection should the locusts fix nitrogen and reach and loblolly are fairly robust and may Anyone wanting to implement be a “best match” with the producer’s harvesting size at an earlier age. tolerate planting into ground cover; silvopastures should “build a team goals and resources. For many, trees however, shortleaf and Monterey will and plan, plan, plan.” will first be part of an animal comfort Layout not fare as well. Even with tolerant Seeking advice from those who strategy – to relieve heat stress in Planning the silvopasture layout species, the release from competition have implemented silvopastures, summer or to provide windbreaks and should not be underestimated. will speed tree growth. working with others who have shelter in winter – or as secondary feed density and spatial For those averse to herbicides, expertise in trees, forages and sources. Others may be as interested arrangements will vary based on the tillage can be used to kill and break up livestock, and getting feedback from in tree products, whether marketed amount of shade the species casts or existing vegetation at establishment. those who contribute to the farm as commodities (e.g., pine straw or the water required. Layout also should Intense grazing pressure may also be operations (e.g., custom applicators) greenery, nuts or fruits) or as value- consider prevailing winds, animal used to weaken forage stands. can save time, money and frustration. added goods (such as wreaths, ciders, movement, infrastructural needs and After planting, mats, mulches Consideration, too, must be given acorn-fattened or apple-fattened hogs). aesthetic appeal. or judicious mowing or grazing can to layout, compatibility with forage Creating wildlife habitat for hunting Clumped arrangements can be be used to suppress vegetation, but species, appropriate protection from leases is another common goal. Of visually appealing and beneficial for herbicides generally have greatest livestock and equipment, and long- course, these aims are all academic some tree species, but most plantings effect and economy for vegetation term management needs. if on-the-ground resources such as are laid out in rows. Thus, row control.

Both soft and hardwood species are suitable for silvopastures, and a multitude of trees and configurations can be utilized. “Warm-season” trees such as locusts, walnuts and members of the hickory family leaf out after the initial flush of cool-season forage growth, thus reducing competition with forages in spring and buffering forages and livestock from high temperatures in summer. Leaves from such trees also degrade more readily than heavy leaves of or maples. Trees in this 2011 picture were thinned by half in 2012. Conifers are well suited to high-density plantings with wide alleys. Photo courtesy of John Fike. Tree protection and management Some additional considerations Tubes rarely are used to protect Silvosystems are dynamic and conifer seedlings. Given low costs of change (and will require input) over the seedlings, high tree density per time. Maintaining adequate light to acre and lower levels of predation, the forage understory may require this would seem uneconomical in thinning or pruning – but this can most cases. In contrast, tubing a have other benefits. hardwood tree typically is standard For instance, trees with clean practice. Whether this truly is boles can have substantially greater needed likely depends on predation timber values when premiums are pressure, but risk of herbivory by available for high-quality logs, and rodents, deer or livestock typically removing small limbs can be done is high, especially with low-density fairly readily during the off season. plantings. Once the trees grow out Although economic analyses are of the tubes, a single hot wire can be limited, greater returns generally positioned about 3 feet from the tree accrue to silvopasture systems that 2 row, allowing cows to graze near the incorporate routine tree maintenance. tree but not to browse the tree itself. Given the state of timber A three-dimensional fence may be economics, producers looking to make adequate to keep deer at bay. Keeping large returns from growing a couple of 1 the wires high enough to allow acres of average-quality timber trees or calf access also can be effective for may face disappointment. However, vegetation management. Of course, even small plantings offer opportunity if fencing is not an option, it may be to improve animal comfort and best to make hay in the alleys until performance, protect environmental the trees are of adequate size to resources and create more appealing integrate with livestock. landscapes while diversifying farm Consider livestock class, age and income streams. condition as well as tree types when The big challenge for making protection decisions. Some implementation is a willingness to studies have shown that mama cows manage complexity and to think in won’t browse slash-pine seedlings time-period scales not common in the if they have adequate forage, and agricultural community. FG trampling losses may be offset by the savings from not protecting the John Fike is a forage, livestock and trees. However, young steers have biofuels specialist with Virginia Tech been observed making a game of and acknowledges the dedication of a pulling newly planted pine seedlings silvopasture team that included Miller from the ground, and bulls will “walk Adams, Jim Burger, J.B. Daniel, Adam 3 down” sizeable pine trees to get a Downing, Jason Fisher, Greg Frey, Tim 4 belly rub. Mize, John Munsell and Chris Teutsch.

PICTURE 1 & 4: Tillage or spraying can be used to reduce vegetative competition for new plantings. Flagging is helpful to indicate which and how many trees go in a row. Several methods can be used to plant trees. Large-scale plantings requiring tubes can be placed by hand with commercial crews at relatively low cost. A mechanical tree planter may be best for establishing long rows of conifers at high density. These trees were planted at 4-feet spacing within rows, 8-feet spacing between rows, with 60-feet alleys. Photos courtesy of John Fike, Todd Groh and Todd Repass. PICTURE 2 Growth often is more rapid in pastures due to greater fertility resources. These 11-year-old loblolly pines were about 15 feet tall. Photo courtesy of Gabriel Pent. PICTURE 3 A good map of the farm or targeted fields can greatly aid silvopasture planning. Knowing soils and boundary dimensions will be helpful for tree selection and placement. GPS systems can be useful for the layout, but in this case, the farmer – a pilot and IBM engineer – used crayons to mark a blow-up of the farm before graduating to permanent markers. Permanent fences placed alongside the tree rows for protection also facilitate rotations, making grazing management easier. Photo courtesy of Gabriel Pent. BELOW: At this site, fescue or switchgrass plus lespedeza are grown in the alleys, providing excellent habitat for quail and other wildlife. Photo courtesy of Gabriel Pent.