Conversion of Solar Energy into Digestible Energy: A Basis for Evaluating Range Forages?

Abstract

Identification of forage species that have high solar energy/digestible energy conversion ratios could lead to the development of forage varieties which produce more digestible energy per unit area of land. This concept was tested by first determining if certain forage species differed in their physiological capability of converting solar energy into a digestible form. The digestible energy conversion efficiency (DECE) of Agropyron cristatum (L.) Gaertn., Agropyron smithii Rydb., Bouteloua gracilis (A.B.K.) Lag., Carex filifolia Nutt., Koeleria pyramidata (Lam.) Beauv. and Stipa comata Trin. & Rupr. was calculated from 1977 field data. Initial results indicated Agropyron cristatum was more efficient (P<0.05) than any of the natives. But correction of digestible energy content for unequal aboveground biomass production reduced species differences to a nonsignificant level.