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Doctorat
États-Unis
1976
Response of five southwestern range plants to season of defoliation
Titre : Response of five southwestern range plants to season of defoliation
Auteur : Miller RF
Université de soutenance : New Mexico State University
Grade : Doctor of Philosophy (PhD) 1976
Résumé
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
Mots Clés : defoliation, fourwing saltbush, defoliation, grasses, plant productivity, plant, Atriplex, plant, Bouteloua, plant, Muhlenbergia, plant, Panicum, plant, Sporobolus,
Page publiée le 25 février 2016, mise à jour le 20 décembre 2019