Oleoresin from Individual Trees of Slash and Longleaf Pine A. P. BLACK AND S. M. THRONSON, University of Florida, Gainesville, Fla. KE yield of oleoresin
T
ably longer period of time the Samples of oleoresin from carefully selected from various American character of the turpentine and individual trees of slash and longleaf pine were conifers has been the subrosin from carefully selected incollected at 2-week intervals. They were disdividual trees of slash and longject of a considerable amount tilled with steam in the usual manner, and the l e a f p i n e as i n f l u e n c e d by of investigation. Re1 a t i v e l y speciJic gravity, index of refraction, and optical weather conditions and by inlittle work has been done, however, on the chemical analysis dividual differences in the trees rotafion of the turpentine determined. of the oleoresin, particularly the themselves. A summary is given of the analytical data obo l e o r e s i n s of Pinus palustris W o r k was b e g u n i n t h e tained from 416 samples of oleoresin. The summer of 1930. The trees are (longleaf) a n d Pinus caribuea average percentage of turpentine obtained from located a t the Southern Forest (slash). Herty (2)reported the slash oleoresin was slightly greater than that Experiment S t a t i o n , Starke, analyses of several samples from Fla., and all identifications and Cuban pine (Pinu8 heterophylla), from longleaf. Large trees yielded slighily higher t r e e s t u d i e s were m a d e b y and Herty and Dickinson (4) percentages of turpentine than small trees. Turforesters of the station. As the reported the average analysis of pentine from slash oleoresin was of lower specific Southern F o r e s t Experiment oleoresin from pine, the species gravity than from longleaf. The optical rotation Station is an official station of of which is not given. Betts (1) of the turpentine was the most variable of the the Weather Bureau, an accurate reported the analyses of many and continuous record of weather samples of oleoresin from western physical constants determined, and significant conditions was available a t all yellow pine (Pinus ponderosa). differences were noted in the rotation of turpentine t i m e s , Considerable attention Schorger (7) reported additional from individual trees. The time of the year at was given to the selection and analyses of oleoresin from the which the oleoresin was collected seemed to exert g r o u p i n g of the trees. They same s p e c i e s . Schorger (9) little or no effect upon any of the physical conwere divided into three groups of reported the analysis of oleofour each, according to size. The resin f r o m s a n d pine (Pinus stants of the turpentine. first group was made up of trees Clausa Sarg). Herty (3) made averaging about 9 inches (22.9 a g r e a t m a n y a n a l y s e s of the oleoresin from both longleaf and slash pine, including cm.) in diameter at breast height,
