Potential adaptability and constraints of response to changing climates for Encelia farinosa var. phenicodonta from southern Baja California, Mexico

To examine the physiological adaptability of Encelia farinosa var. phenicodonta from southern Baja California, plants from Todos Santos, BCS were raised in central Arizona where winter-spring precipitation is greater than typically experienced by this variety. Plants were capable of high photosynthetic rates during the cool and wet spring months and showed substantial growth and reproductive output. Winter freezes caused severe stem dieback and even plant death. These findings suggest that freezing temperatures may influence the restricted and disjunct distribution of E. farinosa var. phenicodonta in the northern part of its range. The growth and reproduction results also imply that this variety may possess the physiological adaptability to thrive under potential climatic changes in southwestern North America.