Riparian Forest Buffers and Silvopasture

Last week, Tim Baker introduced the topic of agroforestry. This is his second post.

Since agroforestry has five areas of interest, I thought I would go into a little more detail on these practices over my next few columns. This week I would like to discuss riparian forest buffers and silvopasture.

Riparian forest buffers involve the use of trees, shrubs, warm seasons grasses, and other plants to protect the areas next to streams, lakes, or other wetlands. There are several advantages of using a correctly-designed riparian forest buffer.

First of all, is the obvious reduction of erosion.  At a recent training that I attended, there were many photos shown of areas where farmers were losing parts of their fields to stream erosion. In the more serious cases, engineers might be needed to design streambank bioengineering or other structures to correct the problem.

The better approach is to try to stop that kind of loss before it gets started.  A good riparian forest buffer will have trees with strong root systems that help stabilize soil near the stream. As you move away from the stream, you will use smaller woody species such as shrubs. And further away, next to your crop or pasture, will be native grasses and forbs. With a system like this, wildlife habitat and water quality will be improved as well.

A riparian forest buffer system can reduce flood damage. Woody buffers reduce the flood water velocity, and help keep debris from entering cropland.

Finally, there is an opportunity to introduce species that produce income. Nut crops, berries, or even craft materials can be grown in a riparian forest buffer.

Silvopasture involves the use of animals in combination with trees and forage in a designed rotational grazing system. Turning out livestock into a forest setting without proper management is not considered silvopasture. Silvopasture uses good management under a designed plan.

Silvopasture practices may be initiated by establishing trees into existing pasture, or by establishing forages into existing woods that have been thinned to increase light penetration. For many producers, silvopasture systems can be a good supplement to their existing pastures. When used properly, they can reduce stress and improve weight gain on your livestock, as well as provide products from the trees.

On a recent field trip, a good example of how a silvopasture system works was described by Dr. Michael Gold, Professor of Agroforestry at the University of Missouri. In research at an MU Experiment Station, Dr. Rob Kallenbach  had found that cattle spending 25% of their time under a rotationally grazed silvopasture system, and the rest of their time under regular rotationally grazed pasture, actually outperformed livestock that spent 100% of their time on pasture under rotational grazing.  This is because cool season grasses actually grow better in a well-designed silvopasture setting in hot weather. At the same time, the livestock found the shade to be less stressful in hot weather. This translated into higher weight gains. In addition, the trees offer a windbreak for winter weather. Eventually, the trees in that system will be harvested for lumber. Now that’s a well-designed system, I think.

Tomorrow Tim will continue with the third of the five agroforestry articles.

(by Tim Baker, MU Extension Horticulture Specialist)