Cupressaceae

Cupressus guadalupensis S.Watson

Endemic to Baja California, Mexico and the border area of California, USA. Threatened by fire and urbanisation.

Distribution

Occurs in Mexico and USA. Mexico: Baja California Norte, Guadalupe Island, also along the border with California; USA: SW California, a few localities in Orange Co. and San Diego Co.

On the mainland, the population consists of >10,000 mature trees, but on Guadalupe Island fewer than 200 remain. The population on the mainland continues to decline, while on the island an increase has recently begun following the eradication of feral goats in 2005.

Habitat and Ecology

In chaparral on slopes with Adenostoma spp., Arctostaphylos sp., in ravines in the Upper Sonoran Life Zone associated with Acer sp., Rhus laurina, Quercus spp., and Arctostaphylos sp., also locally associated with Pinus radiata var. binata; often along intermittent streams on loamy, sandy, gravelly or rocky soils (or 'adobe soil') over sandstone or granite in full sun. The altitudinal range of var. guadalupensis is from 800 to 1280m and var. forbesii from 210 to 1400 metres above sea-level. The climate is a Mediterranean type with dry, hot summers and winter rain; with frequent fog on Guadalupe Island.

Human Uses

No uses are known of this species and its varieties. Only a few botanical collections in California (e.g. Rancho Santa Ana Botanical Garden) have grown this species successfully. It should be taken into cultivation more widely especially for reasons of ex situ conservation of the variety native to Guadalupe Island.