Effect of Phenology on Total Available Carbohydrates and Crude Protein in Tobosagrass

Total available carbohydrate and crude protein content of tobosagrass (Hilaria mutica) was monitored in relation to phenology in the 'Irans-Peeos region of Texas. The im-mature leaf, mature leaf, culm elongation, boot, anthesis, seed, and winter dormancy stages were evaluated. Total available carbohydrates only were measured in roots and crowns. Stems and leaves showed an initial crude protein level of 6.88% which dropped throughout the plant's development to 4.75%. Root and crown carbohydrates showed an initial level of 19%. Shifts in carbohydrates between stems and leaves, roots, and crowns oceured throughout the growing season. Root and crown carbohydrates dropped significantly (to 11% and 9% respectively) before and dur-ing seed production, but regained early season levels before dormancy.