Some Clues to Great Basin Postpluvial Climates Provided by Oak Distributions
Cottam WP, Tucker JM, Drobnick R. 1959. Some Clues to Great Basin Postpluvial Climates Provided by Oak Distributions. Ecology. 40(3):361-377
Hybrids between Quercus gambelii and Q. turbinella have been found on the foothills of the Oquirrh and Wasatch Mountains in north-central Utah and at scattered localities on lower mountain slopes along the eastern boundary of Pluvial Lake Bonneville. The hybrids are intermediate in morphology and in length of leaf persistence. The postpluvial Altithermal period of Antevs, marked by a warmer and drier climate than at present, provided the necessary conditions for the northward migration of Q. turbinella. Continuous temperature records were taken over a period of one year at eight stations to gather data which would provide (1) the thermal requirements of Q. turbinella and the hybrids, and (2) a basis for reconstructing the climate of the Altithermal period. The data obtained suggest that the temperature factor(s) responsible for the disappearance of Q. turbinella from the Great Basin with the onset of the present climate was not a general decrease in temperature throughout the year nor colder winter minimal temperatures, but a significant drop in total warmth during a period from late fall to early spring.
- Type
- Journal Article
- Authors
- Cottam, Walter; Tucker, John; Drobnick, Rudy
- Units
- PARA
- Keywords
- Distribution, Fagaceae (Oaks), Fagales, Lake Bonneville, Quercus gambelii (Gambel Oak Gambel's Oak), Quercus turbinella (Scrub Oak Shrub Live Oak Sonoran Scrub Oak Turbinella Oak), relict, Temperature, Vascular Plant, Wisconsin glaciation