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6980275 
Journal Article 
Growing quality forages under variable environmental conditions 
Buxton, DR; , 
1995 
UNIVERSITY ALBERTA DEPT AGR, FOOD & NUTR SCI 
EDMONTON 
123-134 
WOS:A1995BJ91J00011 
Forage age and maturity generally have a larger influence on forage quality than environmental factors. Plant environment, however, cause deviations in forage quality even when harvested at the same maturity. Temperature usually has greater influence on forage quality than other environmental factors. Although increasing temperature normally hastens maturity, the primary effect may be through its effect on the leaf/stem ratio with high temperatures promoting stem over leaf growth. Digestibility of both leaves and stems is lowered by warm temperatures because of resulting high cell-wall [estimated by neutral detergent fiber (NDF)] and low soluble sugar concentrations.Some other stresses slow plant maturation, which results in herbage quality being maintained at high levels for a longer time. This is illustrated by the effects of drought and insect damage on forages. Both cause a reduction in leaf mass. If the loss of leaves is not severe, these stresses may have little effect on forage quality or may actually improve forage quality. Forage grown under shaded conditions usually has higher crude protein concentrations than unshaded forage. Diurnal variation also exists in forage quality with highest quality in the late afternoon as a result of photosynthate accumulation, which dilutes cell-wall concentration and lowers NDF. Soil nutrients only have small effects on forage quality. Nitrogen fertilization usually raises the crude protein concentration of nonlegume forages. Foliar diseases and plant pests probably have the greatest adverse effect on ii forage quality by reducing digestibility. Some weeds reduce forage quality but many have nutritive values similar to forages and have little impact on forage quality. 
Kennelly, J; 
1-896110-03-7 
13th Annual Western Canadian Dairy Seminar (WCDS) 
RED DEER, CANADA