Date of Award


Document Type

Masters Thesis

Degree Name


Organizational Unit

College of Natual Science and Mathematics

First Advisor

Donald G. Sullivan, Ph.D.

Second Advisor

Martin F. Quigley

Third Advisor

J. Michael Daniels

Fourth Advisor

Hillary B. Hamann


Climate, Dendroecology, Episodic recruitment, Palmer Divide


Previous recruitment studies on populations of ponderosa pine (Pinus ponderosa P. & C. Lawson) in Colorado have been limited to the western mountains and the Front Range. In this research I used tree-ring data to reconstruct recruitment for ponderosa pine near the eastern limits of its distribution at two sites on the Palmer Divide, Eastern Colorado, to determine the relative climate sensitivity of the two sites, and the extent to which climate or other factors may have influenced recruitment at the sites. The results of the tree-ring analysis suggest that ponderosa pines in more the easterly site lower elevation population are more sensitive to climatic factors than are in the more westerly site. Both higher elevation populations showed a history of episodic recruitment that only partially reflects local climatic conditions. Climate is probably the most important factor in recruitment pulses, but only if there is opportunity within the stand for recruitment. Although favorable climate patterns were present at both sites at the same time, the opportunity for recruitment within each stand was different at separate times. While climate conditions must be favorable for seedling establishment and growth, conditions of stability and competition within the stand dictate the ultimate recruitment success.

Publication Statement

Copyright is held by the author. User is responsible for all copyright compliance.

Rights Holder

William Henry Brenton Jr.


Received from ProQuest

File Format




File Size

63 p.


Geography, Paleoecology, Paleoclimate science