The germination of bitterbrush (Purshia tridentata) seeds in relation to constant and alternating temperature regimes was investigated. The germination of untreated, stratified, and thiourea-treated seeds was compared. Germination of untreated seeds was greatest with cold (night) temperatures in the optimum range (2 degrees to 5 degrees C) for stratification. Warm (day) temperatures of 10 degrees to 40 degrees C gave relatively high germination when the night temperatures were in the stratification range. Thiourea treatment greatly expanded the number of temperature regimes that gave maximum germination. Thiourea treatment also increased the amount of germination, both in the optimum temperature range and at suboptimal or superoptimal ranges. Stratification enhanced germination of bitterbrush seeds, but the magnitude of response in relation to temperature regimes was not identical to enhancement with thiourea treatment. This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries. The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact lbry-journals@email.arizona.edu for further information. Migrated from OJS platform August 2020
Scholarly peer-reviewed articles published by the Society for Range Management. Access articles on a rolling-window basis from vol. 1, 1948 up to 5 years from the current year. Formerly Journal of Range Management (JRM). More recent content is available by subscription from SRM.