Relationship of Organic Reserves to Herbage Production in Crested Wheatgrass

Abstract

The weight of etiolated growth stimulated in the field by excluding sunlight from crested wheatgrass plants was measured and used as a quantitative index to the organic reserves of plants prior to spring growth. Subsequent herbage yields and vegetative/reproductive tiller composition were measured and statistically compared with the etiolated growth. Etiolated growth, basal area per plant, and number of tillers per unit surface area were all highly correlated to the subsequent herbage production. Protection from grazing for one growing season is apparently sufficient time for crested wheatgrass plants to nearly replenish their organic reserves. The use of etiolated growth in predicting herbage yields may be applicable when organic reserves are the most limiting growth factor.