@article {51213, title = {Relationship of tarbush leaf surface terpene profile with livestock herbivory}, journal = {Journal of Chemical Ecology}, volume = {24}, number = {1}, year = {1998}, month = {January 1, 1998}, pages = {1-12}, abstract = {

Tarbush (Flourensia cernua DC.) is a Chihuahuan Desert shrub with a resinous leaf surface containing terpenes that may affect livestock herbivory. Cattle, sheep, and goats were densely stocked in paddocks containing tarbush in two consecutive years for six to nine days and defoliation of 160 plants was recorded daily. Plants were categorized as exhibiting high or low defoliation. Leaves were collected from these plants the third year for chemical analysis. A selection procedure was used to generate two variable sets closely related to defoliation category. One set contained 14 variables (dry matter, ash, -pinene, sabinene, 3-carene, p-cymene, limonene, camphor, bomeol, cis-jasmone, {\^a} -caryophyllene, alpha-humulene, ledene, and flourensadiol) and the other set contained 14 unidentified compounds. When subjected to multivariate analysis, each group distinguished between the two defoliation categories (P \<0.001 and P \<0.0019 for known and unknown variable sets, respectively). These data support the hypothesis that leaf surface chemistry of individual tarbush plants is related to extent of defoliation by livestock.

}, keywords = {diet selection, Epicuticular wax, Flourensia cernua, leaf surface chemistry, monoterpenes, sesquiterpenes}, doi = {10.1023/A:1022399426352 }, url = {/files/bibliography/608.pdf}, author = {Richard E. Estell and E.L. Fredrickson and D.M. Anderson and Kris Havstad and M.D. Remmenga} } @article {51322, title = {Tarbush leaf surface terpene profile in relation to mammalian herbivory}, year = {1996}, note = {NOT A DUPLICATE OF RECORD $\#$474}, month = {1996}, pages = {237-241}, publisher = {US Forest Service}, edition = {Gen. Tech. Rep. INT-GTR}, abstract = {

Cattle, sheep and goats were densely stocked in pad- docks 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 ana-lyzed 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, a copaene, B caryophyllene, a 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 related to degree of defoliation of individual tarbush plants by livestock.

}, keywords = {diet selection, Epicuticular wax, Flourensia cernua, leaf surface chemistry, monoterpenes, sesquiterpenes}, url = {/files/bibliography/512.pdf}, author = {Richard E. Estell and E.L. Fredrickson and D.M. Anderson and Kris Havstad and M.D. Remmenga} } @article {51440, title = {Secondary chemistry of the leaf surface of Flourensia cernua}, journal = {Biochemical Systematics and Ecology}, volume = {22}, number = {1}, year = {1994}, month = {1994}, pages = {73-77}, abstract = {

Epicuticular wax accounted for 9.2\% fo the dry weight of whole Flourensia cernua (tarbush) leaves. Leaf surface extracts of tarbush were analyzed for mono- and sesquieterpenoids with gas chromatography/mass spectrometry. Camphene, $\#$ mycrene, 3-carene, limonene, 1,8-cineole, borneol, cis jasmone, $\#$ caryphyllene, caryophyllene oxide and globulol were consistently present in tarbush. Concentrations of several unidentififed compunds were estimated. A great deal of plant to plant variability was detected in leaf surface mono= and sesquietepenoid concentration. Infomation obtained on surface chemistry might be exploited to enhance use of tarbush as a forage for domestic herbivores.

}, keywords = {epicuticular waxes, Flourensia cernua, leaf surface chemistry, monoterpenoids, sesquiterpenoids}, doi = {10.1016/0305-1978(94)90116-3}, url = {/files/bibliography/419.pdf}, author = {Richard E. Estell and Kris Havstad and E.L. Fredrickson and Gardea-Torresdey, J.L.} }