Management and ecology of redberry juniper in the Texas rolling plains

Redberry juniper (Juniperus pinchotii Sudw.)historically occurred on rocky, shallow sites in limestone or gypsum soils. It has increased in density on these areas and has expanded to adjacent grasslands. The suppression of wildfires, overgrazing, and the ability of the species to adapt have promoted this invasion. Redberry juniper is a basal sprouting, multi-stemmed evergreen. The ability of redberry juniper to resprout makes control difficult. Redberry juniper is considered an invader on most range sites and has little economic value. However, redberry juniper is desirable on some range sites because it stabilizes the soil and provides wildlife cover.

A study at Justiceburg, Texas, on two range sites, clay flat and shallow redland, evaluated the response of redberry juniper to varying concentrations of picloram, and investigated the stem diameter-age relationships, growth dynamics and establishment history of redberry juniper. Trees were mechanically and/or chemically treated in July, 1996, and evaluated at the conclusion of the 1997 growing season. Labor and capital costs were evaluated for each treatment to determine the most economical method for managing redberry juniper. The leader stem with the largest diameter was mechanically removed and the annual growth rings counted to determine age. Prediction equations were developed from this information and stem diameter-age relationships determined. The objectives of this study include: (1) determine mortality of redberry juniper following different treatment regimes, (2) determine the cost for each treatment, (3) develop economical, practical, and sound recommendations for redberry juniper management, (4) assess the stem diameter-age relationship of redbeny juniper, and (5) evaluate the growth dynamics and determine the establishment histor} of redberry juniper.