Browsing Journal of Range Management, Volume 38, Number 3 (May 1985) by Authors
Evaluation and Management of Grasses for Dual Livestock and Game Bird UseHolt, E. C.; Cain, J. R.; Hendler, R. J. (Society for Range Management, 1985-07-01)Kleingrass 75 and Verde kleingrass (Panicum coloratum L.), PI 217229 and PMT 4022 plains bristlegrass (Setaria macrostachya H.B.K.) Nees), and commercial green sprangletop (Leptochloa dubia (H.B.K.), were studied for forage and seed production. Acceptability of seed was studied using caged bobwhite quail (Colinus virginianus). Defoliation management practices had relatively little influence on forage yield. Forage digestibility declined rapidly when defoliation was delayed, and the species responded differently in the rate and pattern of decline. Seed yields were as high or higher with 30-day interval harvesting as with deferred harvesting except that spring deferment increased kleingrass and summer deferment increased green sprangletop seed yields. Green sprangletop also produced more seed by leaving a 20-cm stubble than a 10-cm stubble. These indeterminate species apparently mature seed in approximately 30 days, indicating that a management system that leaves some tillers intact for 30 days or longer will result in some seed formation. Seed production decreases to nil in 2 to 3 months following first maturity in an undefoliated stand. Bobwhite quail readily consumed kleingrass seed as a significant portion of their diet even in the presence of a high quality game bird diet. They subsisted for short periods on an all grass seed diet, but consumed little plains bristlegrass or green sprangletop when game bird diet, pearl millet, or kleingrass were present. Thus, kleingrass has the most potential of the species studied for dual use.
Temperature and Water Stress Effects on Growth of Tropical GrassesBade, D. H.; Conrad, B. E.; Holt, E. C. (Society for Range Management, 1985-07-01)Coastal bermudagrass (Cynodon dactylon (L.) Pers.) and Kleingrass "75" (Panicum coloratum L.) were grown under controlled environments to evaluate the effects of high growth temperatures and water stress on forage growth. Plants were grown under a controlled environment with 14/10 hour day/night temperatures of 30/20, 35/25, and 40/30 degrees C; 2 water regimes; and 3 stages or ages of regrowth at harvest. High growth temperatures significantly (P<0.05) increased dry matter yield and accelerated tiller number and the maturation rate of the plants. Significant (P<0.05) increases in leaf area, weight per tiller, and plant height were observed as growth temperatures were increased. Reduction of number of tillers per pot due to water stress reduced dry matter yields approximately 38%. The percent leaf was greater for the water-stressed plants than for the well-watered plants, but the leaf area per plant was less due to reduction of growth and delayed maturation. Dry matter yield of water-stressed plants grown under higher temperatures increased more than corresponding well-watered plants as a result of increased rate of stem elongation and leaf development. Though water-stressed plants were shorter and had less leaf area than well-watered plants, the relative increase in both height and leaf area at higher temperatures of stressed plants was greater than well-watered plants. Apparently supraoptimal temperature (40 degrees C) does not have a negative effect on yield in the presence or absence of moisture stress.