Author
Estell, Richard - Rick | |
Frederickson, Eddie | |
Anderson, Dean | |
Havstad, Kris | |
REMMENGA, MARTA - NEW MEXICO STATE UNIV |
Submitted to: Wildland Shrub Symposium Proceedings
Publication Type: Proceedings Publication Acceptance Date: 3/4/1996 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: Cattle, sheep and goats were densely stocked in paddocks containing tarbush (Flourensia cernua DC) for six to nine days and defoliation of 160 plants was recorded daily during two years. Plants were separated into high, moderate or low defoliation categories. Leaves were collected from plants during the same stage of maturity during the third year. Leaf surface compounds were extracted with ethanol and mono- and sesquiterpenes were analyzed using gas chromatography/ion trap mass spectrometry. A set of 11 variables was identified that appeared most closely related to plant defoliation categories: dry matter, ash, limonene, camphor, borneol, alpha copaene, beta caryophyllene, alpha pinene, p-cymene, cis-jasmone and caryophyllene oxide concentrations. This group distinguished among all three defoliation categories (P < 0.03) when subjected to multivariate analysis. These data support the hypothesis that leaf surface chemistry is srelated to degree of defoliation of individual tarbush plants by livestock |