[thornforest]

My hillside garden is located on the northern slopes of a large hill in Spring Valley , California. This is near the site, some more seasoned San Diego plant growers may recall, of the old "Palms Nursery" begun first in Nestor, then moved to this hill sucessfully, after WW2. I would consider this a 10a/10b zone. Temps have fallen to lower 40's F. at ground level since I have been here. I did have the upper 10 feet of my +/- 35 foot high Mai Nung Bamboo have temporary leaf die - back when many coastal areas had frost but no frost visible on any plants or the ground here. No die back has ever been seen during this time of Mallosma laurina on this site which is a coastal sagebrush- habitat -native and sensitive to frost. I have observed Mallosma laurina die back closer to the coast following frost in East and Central San Diego. I moved here in 1992 from San Diego. I have never observed frost on this particular ridgetop. Fingers crossed. There seems to be some evidence for a micro climate associated with certain inland hills of San Diego County.