THE AUTHORS 



RESEARCH SUMMARY 



WALTER E. COLE is Project Leader of the Population Dyna- 

 mics of the Mountain Pine Beetle research work unit in 

 Ogden, Utah. This unit was started in 1960 under his direc- 

 tion, as was the early research groundwork on the mountain 

 pine beetle. Prior to this assignment, he did population 

 dynamics research, control, and survey work on the spruce 

 budworm and pine butterfly in southern Idaho. He did biolo- 

 gical research and survey data collection on the spruce bark 

 beetle in Fort Collins, Colorado. He began his career with 

 Forest Insect Investigations, Bureau of Entomology and Plant 

 Quarantine, as supervisory control and survey aid in 

 Berkeley, California. Dr. Cole has authored 31 publications. 



E. PARK GUYMON is Professor of Chemistry at Weber State 

 College, Ogden, Utah. He received his Ph.D. in analytical and 

 inorganic chemistry from Utah State University. His research 

 activities have covered many interesting and practical 

 aspects in the analysis of natural products and nitrogen fixa- 

 tion. Dr. Guymon's publications are well-known in these fields 

 of interest. 



CHESTER E. JENSEN, retired, served as principal statistician 

 for the Intermountain Forest and Range Experiment Station 

 from 1967 to 1980. He held the same position at the North- 

 eastern and Central States Forest Experiment Stations prior 

 to coming to the Intermountain Station. 



Phloem samples taken from 86 healthy lodgepole pine trees 

 at three points in the 1975 growing season were analyzed for 

 content of dry matter, starch, various forms of sugar and nit- 

 rogen, and of selected monoterpenes. Means for July 1 and 31 

 were significantly lower than those of June 6 for dry matter, 

 soluble reducing sugars, nitrogen, and monoterpenes. 

 Starches and other sugars were higher, p-phellandrene was, by 

 far, the most prevalent of the monoterpenes. Dry matter in the 

 phloem contained an extremely small amount of monoterpene 

 by weight but, of this, individual monoterpenes were distributed 

 in about the same proportions found in pure oleoresin by other 

 researchers. Monoterpene contents from the last (July 31 ) sam- 

 ples were significantly, although weakly, related to the linear 

 positive effects of phloem thickness and radial growth. An inter- 

 active hypothesis is developed for terpene content as a function 

 of phloem thickness, radial growth, and tree diameter. Here, 

 high concentrations of monoterpenes coincide with larger tree 

 diameters, the expected region of high mountain pine beetle 

 survival. 



CONTENTS 



Page 



INTRODUCTION 1 



MATERIALS AND METHODS 1 



DATA ANALYSIS AND HYPOTHESIS 2 



RESULTS 6 



DISCUSSION 6 



APPENDIX 7 



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