Strategies for Successful Germination of Rocky Mountain Juniper (Juniperus scopulorum Sarg.) in an Oklahoma Nursery

Abstract

Low and inconsistent germination of Juniperus scopulorum in nurseries limits successful production of this species. The objectives of this study were to determine suitable pregermination protocols that would help to germinate and establish J. scopulorum at the Oklahoma Forest Regeneration Center so it could be grown as an alternative windrow species in the state of Oklahoma. In the first year of the study, one seed source of J. scopulorum was used with seven stratification treatments applied. Stratified seeds were planted in the nursery at two depths in both December and March. In April and July, the seedlings were counted to determine which stratification treatment produced the most germinants. Germination tests and `in stratification' counts were also conducted. In the second year of the study, the best stratification treatments were applied to six seed sources of J. scopulorum to determine seed source variability in germination success. 13 weeks of warm stratification and 13 weeks of cold stratification (13W/13C) and 13 weeks of cold stratification (13C) were the best treatments from year one of the study with greater overall success with the December planting than the March planting. Planting depth did not affect seedling production. The 13W/13C treatment was by far the best treatment on all six seed sources used in year two of the study. The Wasta, SD seed source of J. scopulorum had the highest germination rate.