Juniperus californica (California juniper; Cupressaceae) occurs in a variety of habitats, including pinyon-juniper woodlands and high elevation desert scrub in the northwestern Sonoran Desert. The goal was to determine how much physiological and structural plasticity and microclimate allow J. californica to survive in desert scrub. We hypothesized that individuals in the desert scrub (Agave Hill) coped with greater water stress by limiting xylem cavitation and exhibiting greater stomatal control than individuals in the pinyon-juniper woodland (Pinyon Crest). Additionally, J. californica were expected to occur in cooler microhabitats in the desert scrub, which should have more available soil water than the surroundings. Hypotheses were tested by examining climate data, as well as the morphology, physiology, wood anatomy, and canopy and soil temperatures for individuals at both sites. Agave Hill received less rainfall and the air and soil temperatures were significantly warmer than at Pinyon Crest. Individuals were larger at Pinyon Crest than at Agave Hill; however, water relations and maximum quantum efficiency of Photosystem II did not differ between sites. Plants at Agave Hill had lower CO₂ uptake in the autumn and suffered greater dieback during the study; stomatal conductance was also lower at Agave Hill. Average native xylem embolism and wood anatomy did not differ with site; however, xylem embolism did increase as plant shoot volume decreased at Agave Hill. The results indicate that J. californica exists in desert scrub by occupying washes and altering its morphology through reduced growth and dieback during stressful periods.

加州杜鹃（Juniperus californica）（加州杜鹃；柏科）存在于多种栖息地中，包括松树杜松林和索诺兰沙漠西北部的高海拔沙漠灌木丛。目的是确定多少J. californica在沙漠灌木丛中能够生存的生理和结构可塑性以及微气候。我们假设沙漠中的灌木丛（龙舌兰山）的个体通过限制木质部的空化并表现出比松树-杜松林地（Pinyon Crest）中的气孔控制更大的水分胁迫。此外，加利福尼亚州J.预计将在沙漠灌丛中较凉爽的微生境中发生，该地区的土壤水应比周围环境多。通过检查气候数据以及两个地点的个体的形态，生理，木材解剖以及冠层和土壤温度来检验假设。龙舌兰山的降雨量较少，空气和土壤温度明显高于Pinyon Crest。Pinyon Crest的人比Agave Hill的大。然而，光系统II的水关系和最大量子效率在两个站点之间没有差异。龙舌兰山的植物的CO ₂较低在秋天摄取并在研究期间遭受更大的死亡；龙舌兰山的气孔导度也较低。普通的原生木质部栓塞和木材解剖结构与地点没有差异。然而，随着龙舌兰山的植物芽减少，木质部栓塞确实增加了。结果表明，加利福尼亚J. californica存在于荒漠灌木丛中，原因是其在胁迫期间通过减少生长和枯萎而占据了洗涤空间并改变了其形态。