You are here: Home / Research Topics / Research Highlights / Individual Highlight

Research Highlights

Individual Highlight

Selecting the right shade-tolerant forages for restoring savannas or woodlands and implementing different agroforestry practices

Photo of Figure 1.—Overview of Shade Tolerance Laboratory for growing and evaluating forage productivity and quality of grasses and legumes under three light intensities (0, 45, and 20 percent of full sunlight) in the absence of competition from tree roots.  Credit?
Figure 2.—Jerry Van Sambeek, an USDA Forest Service research plant physiologist, examines growth of Virginia wildrye grass grown in an outdoor structure covered by shade cloth to evaluate effects of dense shade (20% full sunlight) on forage production and quality. 
Figure 1.—Overview of Shade Tolerance Laboratory for growing and evaluating forage productivity and quality of grasses and legumes under three light intensities (0, 45, and 20 percent of full sunlight) in the absence of competition from tree roots. Credit? Figure 2.—Jerry Van Sambeek, an USDA Forest Service research plant physiologist, examines growth of Virginia wildrye grass grown in an outdoor structure covered by shade cloth to evaluate effects of dense shade (20% full sunlight) on forage production and quality. Snapshot : Establishing ground covers is a common practice used in agroforestry, silvopasture (combining forestry with grazing), and savanna and woodland restoration efforts. Forest Service scientists investigated the importance of shade tolerance when selecting legumes and grasses for these efforts.

Principal Investigators(s) :
Van Sambeek, J.W."Jerry" 
Research Location : Columbia and New Franklin, MO
Research Station : Northern Research Station (NRS)
Year : 2017
Highlight ID : 1238

Summary

Ground covers of forage, native grasses, and legumes provide nutrients, especially nitrogen, to facilitate tree growth. Selection of these species for use as ground covers is enhanced when shade tolerance of the ground covers is known. Forest Service scientists screened 43 species of native and introduced legumes and grasses multiple times under three levels of shade cloth in the absence of competition from tree roots. They found that annual biomass yields for all forages did not statistically differ when grown under 45 and 100 percent of ambient sunlight. Thirty-one of the species also had no statistical differences in annual yields when grown under 20 and 100 percent of ambient sunlight. When shade tolerance was measured as yield under different light intensities, cool-season grasses were found to have the greatest shade tolerance. Cool-season legumes had the least shade tolerance, while warm-season grasses and legumes were on average intermediate to the cool-season forages. Research results suggest most forages can perform as well under shade of open-grown trees (if tree root competition can be minimized) as under full sun, providing land managers with a wide selection of forage and legume species they can use to achieve desired results when implementing agroforestry practices or restoring savannas or woodlands.

Forest Service Partners

External Partners

 
  • University of Missouri Center for Agroforestry, Natural Resources Conservation Service

Strategic
Program Areas

Priority
Areas