Considerable intraspecific variation was found in the monoterpene composition of the wood oleoresin of Pinus coulteri, P. contorta, P. washoensis, and P. jeffreyi. This paper reports data based on the analysis of 20 to 128 trees per species; except for P. contorta, sampling covered a large portion of the range of each species. In general, there were no distinctive geographical variations, but all except P. jeffreyi had appreciable local variation: P. coulteri in α-pinene, -phellandrene, and myrcene; P. washoensis in -pinene, 3-carene, and myrcene; P. contorta in -phellandrene, 3-carene, and -pinene. Measurable or trace amounts of sabinene were found in all species except P. washoensis. One unknown compound, tentatively identified as α-thujene, was found in P. washoensis and P. contorta. Another unknown compound, tentatively identified as terpinolene, was found in all species; it varied in quantity in direct proportion to the amount of 3-carene. P. jeffreyi monoterpene consisted of 88 to 99 percent heptane, with measurable or trace amounts of several other monoterpenes.
Document Type: Journal Article
Entomologist, Pacific Southwest Forest and Range Expt. Sta., Forest Service, U.S. Dept. Agric., Berkeley, Calif.