Pistacia atlantica Atlas pistache

Pistacia atlantica, Jasper Ridge Biological Preserve. Sairus Patel, 5 Nov 2024

Unlike the popular Chinese pistache, which is noted for its fall color, the African species is less showy and can even be semievergreen in protected locations such as Frost Amphitheater. There stands a large specimen about 30 feet tall, with dark roughly checkered bark, on the slope near the intersection of pathways near the east side of the stage (map pin). The species appeared in a 1956 checklist of plantings at Frost; this is possibly from that era. Another of similar girth is on the outer side of the Frost embankment. You can see it on the right, behind the wall, as you walk south along the path at the northwest corner of Arrillaga Alumni Center (map pin).

Several male and a female tree may be seen at Jasper Ridge Biological Preserve, where it is evidently weedy. One that has striking vermilion fall color is on Lakeshore Drive, on the left, about 70 feet after you take the first left turn upon entering the Preserve (map pin). On the Preserve, its somewhat bluish, pinnately-compound, alternate leaves distinguish it from native trees and shrubs. According to Sunset Western Garden Book, it isn’t common as an ornamental but is widely used as understock for pistachio nut.

Illustrations: Jasper Ridge photos.