Limited to approximately 200 acres (81 ha), the only two known occurrences of this type are near the towns of Ben Lomond and Bonny Doon in Santa Cruz County.
This forest type is restricted to very sandy Zayante soils that are isolated pockets of decomposing sandstone from the Miocene terraces of the coastal range, distinct from the volcanically formed rocks which make up most of the Santa Cruz Range.
These soils are deemed to be relicts of once larger expanses found when this region was geologically even younger, and hence had more evidence of the sandstone erosion of the ancient uplifted ocean floor.
Estimated to originally cover 6,000 acres (2,400 ha), 40% of this type has been lost, mostly to sand quarrying and development.
One of these three forests is located atop a ridge that straddles the Carbonera Creek and Zayante Creek watersheds[1] of Santa Cruz County within the western slopes of the Santa Cruz Mountains.