About Cupressus sargentii Jeps.
Hesperocyparis sargentii, originally published under the scientific name Cupressus sargentii Jeps., is a conifer species in the Cupressaceae family, commonly called Sargent's cypress. This species is endemic to California, ranging from Mendocino County south to Santa Barbara County, and grows only in the Coast Range mountains. It can be found in conifer forests, chaparral, and other mountain habitats, and usually forms pure stands on serpentine soils. It typically reaches 10 to 15 meters (33 to 49 ft) tall, though some individuals can grow over 22 meters (72 ft). On Carson Ridge in Marin County and Hood Mountain in Sonoma County, this species forms a pygmy forest where trees do not grow taller than 240–360 cm (7.9–11.8 ft), due to high mineral concentrations in the local serpentine soil. A well-known population of this species grows in the Cedar Mountain Ridge area of Eastern Alameda County. Carl Wolf, who carried out extensive research on New World cypresses in the 1930s and 1940s, recorded that seed collected from the Cedar Mountain stand of Cupressus sargentii produced the most vigorous seedlings. Like many New World Cupressaceae, Sargent's cypress most often reproduces with the help of wildfire: wildfire opens the species' cones and exposes bare mineral soil for seedling germination. Occasional germination of fallen seeds can occur without fire, but this is uncommon rather than the norm. In any given stand of Sargent's cypress, many trees are usually the same age, leading to stratified colonies where each colony consists of same-age individuals. Sargent's cypress can start producing cones as early as five to six years of age.
