Response of five southwestern range plants to season of defoliation

Title	Response of five southwestern range plants to season of defoliation
Publication Type	Thesis
Year of Publication	1976
Authors	Miller RF
Number of Pages	104
Date Published	1976
University	New Mexico State University
City	Las Cruces, New Mexico
Thesis Type	Ph.D. Dissertationpp
Call Number	00551
Keywords	defoliation, fourwing saltbush, defoliation, grasses, dissertation, dissertations, plant productivity, plant, Atriplex, plant, Bouteloua, plant, Muhlenbergia, plant, Panicum, plant, Sporobolus, theses, thesis
Abstract	The objectives of this study were to (1) measure seasonal carbohydrate levels for five species occurring on Southwestern desert rangelands, (2) determine how six different defoliation patterns affect carbohydrate reserves, production, and plant growth characteristics on these five species, and (3) correlate defoliation patterns with plant phenology to maintain healthy productive plants and attain maximum forage yields. The plant species studied were black grama (Bouteloua eriopoda (Torr.) Torr.), mesa dropseed (Sporobolus flexuosus (Thurb. Rydb.)), bush muhly (Muhlenbergia porteri Scribn.), vine mesquite (Panicum obtusum H.B.K.), and fourwing saltbush (Atriplex canescens (Pursh.) Nutt.).... A high level of variability in TAC concentrations between plants generally made levels insensitive to clipping treatments. After three years of clipping only two of the five species, mesa dropseed and bush muhly, showed a significant decline in TAC levels when clipping continuously or after flowering. Physical measurements on grasses such as yield, crown diameter, stolon numbers, and number of elongated internodes were more sensitive to treatment effect. However, in fourwing saltbush the presence of considerable heterogeneity in both morphology and TAC levels within the stand made interpretation difficult.