A silvopasture system is an agroforestry system specifically designed for the production
of trees, tree products, forage for grazing and livestock. Research has shown that
silvopasture systems can be an environmentally and economically feasible alternative to
traditional land uses.
Two potential silvopasture forage species, perennial ryegrass (Lolium perenne L.) and red
clover (Trifolium pretense L.), were exposed to shade, low water levels and varying
species mixes. They were grown in a greenhouse for 14 weeks and were harvested at two
occasions. The light treatments were full light, 50% shade or 80% shade. The water
levels were either a well watered treatment or a water level where the plants were
exposed to water stress. There were three different species mixes; 75% grass / 25%
clover, 50% grass / 50% clover or 25% grass / 75% clover. After harvest the biomass was
measured, development stage determined, and protein content and neutral-detergent fiber
(NDF) content analyzed. The objectives of the study were to investigate how a grass
species and a legume species in different mixes are affected by different levels of shade
and water.
The biomass increased with increased light and water. The grass dominated mix gave a
higher biomass than the clover dominated mix for both species. Only the clover showed
differences in development stages between the treatments. The maturity of the plants was
increased by increased exposure to water and light. In the second harvest both the grass
and the clover increased their protein concentration when the shade levels increased. The
grass had a higher protein concentration when grown in a low water treatment while the
clover had a higher protein concentration when grown in a high water treatment. The
grass dominated mix increased the protein concentration for the grass while the clover
dominated mix increased the protein concentration for the clover. The actual amount of
protein in the plants followed the variations of the biomass; a larger plant had a higher
protein content and vice versa. The NDF levels varied between treatments, crops and
harvests.
The second harvest generally showed larger effects of the tre...
