@article {JRN53927,
	title = {Is differential use of Juniperus monosperma by small ruminants driven by terpenoid concentration},
	journal = {Journal of Chemical Ecology},
	volume = {40},
	year = {2014},
	month = {02/2014},
	pages = {285-293},
	chapter = {285},
	abstract = {<p>We examined the relationship between volatile plant secondary metabolite concentrations and Juniperus monosperma herbivory by small ruminants. Two groups of animals (10 goats or 5 goats plus 4 sheep) browsed 16 paddocks (20 x 30 m) containing one-seed juniper for six days during two seasons. Juniper leaves were sampled from 311 saplings on the same day they were browsed. Saplings were categorized by size (short [\&lt; 0.5 m], medium [0.5-1.0 m] or tall [\&gt; 1.0 m]) and browsing intensity (light [\&lt; 33\%], moderate [33-66\%] or heavy [\&gt; 66\%]). Juniper bark was also collected from 12 saplings during spring. Total estimated terpenoid concentrations in leaves and bark were 18.3 \&plusmn; 0.3 and 8.9 \&plusmn; 0.8 mg/g, respectively, and the dominant terpene in both tissues was a-pinene (11.1 \&plusmn; 0.2 and 7.6 \&plusmn; 0.7 mg/g, respectively). Total terpenoid concentration was greater (P \&lt; 0.001) in spring than summer (20.6 \&plusmn; 0.5 vs. 16.7 \&plusmn; 0.3 mg/g, respectively) and lower (P \&lt; 0.001) in short saplings than medium or tall saplings (16.5 \&plusmn; 0.6 vs. 19.8 \&plusmn; 0.4 and 19.5 \&plusmn; 0.4 mg/g, respectively). Total concentration also differed (P \&lt; 0.001) among the three defoliation categories (16.1 \&plusmn; 0.4, 18.7 \&plusmn; 0.5, and 21.2 \&plusmn; 0.6 mg/g for heavy, moderate, and light, respectively). The smallest subset of terpenes able to discriminate (P \&lt; 0.001) between heavy and light browsing intensity categories included eight compounds ([E]-\&szlig;-farnesene, bornyl acetate, \&$\#$39;-eudesmol, endo-fenchyl acetate, y-cadinene, a-pinene, cis-piperitol, and cis-p-menth-2-en-1-ol).</p>
},
	keywords = {goats, herbivory, one-seed juniper, Oxygenated terpenes, Resource availability hypothesis, sheep, targeted grazing, terpenes},
	doi = {10.1007/s10886-014-0389-1},
	url = {/files/bibliography/14-006.pdf},
	author = {Richard E. Estell and S. A. Utsumi and Andr{\'e}s F. Cibils and D.M. Anderson}
}
