Continuation of Studies on the Dendrochronology of Bristlecone Pine (Pinus aristata Englem.) (Continuation of Research Grant NSF-G 19949): A Research Proposal

The original research grant NSF-G 19949, effective October 1, 1961, for the dendrochronology of bristlecone pine has made it possible: (1) to develop a workable chronology extending back 3850 years, (2) to carry out studies of tree growth as related to environmental parameters through two field seasons, and (3) to make some statistical comparisions which indicate (a) that there is no significant difference between young and old trees in radial growth response to environmental variables, (b) that there are significant correlations between bristlecone pine and other coniferous species extending up to 1000 miles east and southeast, and (c) that there is strong evidence that bristlecone pine will provide a good basis for extending climatic interpretations to at least 2600 B.C.The present request is for funds: (1) to complete an exact chronology made possible through the study of both living and dead material in the White Mountains of California; (2) to extend the chronology building to other key tree-ring areas in the Colorado River Basin with the aim of determining the past climatic chronology; (3) to statistically evaluate the various chronologies thus established for interrelations with climate and with other tree-ring series; (4) to continue the environmental studies and evaluations through a third growing season, 1964; (5) to determine the biological model of cause and effect and its statistical counterpart for estimating climate from these tree-ring series; and (6) to provide for the closely integrated radiocarbon analysis of tree-ring material.The results will be used (1) to strengthen dendrochronological dating and to provide a master tree-ring chronology which can be used by climatologists, archaeologists, radiocarbon investigators, and others; (2) to strengthen and geographically extend the dendroclimatological studies of Schulman (1956), especially in the Colorado River Basin; (3) to provide, when integrated with various environmental studies now being conducted, a stronger basis for environmental interpretations, based on the difference in radial growth shown by trees that respond primarily to differences in precipitation. This information will be of great value to meteorologists, hydrologists, and others, including the Inter-Union Commission on Solar and Terrestrial Relationships.