| Hesperocyparis sargentii | |
|---|---|
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Scientific classification | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Gymnospermae |
| Division: | Pinophyta |
| Class: | Pinopsida |
| Order: | Cupressales |
| Family: | Cupressaceae |
| Genus: | Hesperocyparis |
| Species: | H. sargentii |
| Binomial name | |
| Hesperocyparis sargentii (Jeps.) Bartel (2009) | |
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| Natural range | |
| Synonyms[3] | |
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Hesperocyparis sargentii is a species ofconifer in the familyCupressaceae known by the common nameSargent's cypress. It isendemic toCalifornia, where it is known fromMendocino County southwards toSanta Barbara County. This taxon is limited to theCoast Range mountains. It grows inforests with other conifers, as well aschaparral and other local mountain habitat, usually in pure stands onserpentine soils. It generally grows 10 to 15 meters (33 to 49 ft) tall, but it is known to exceed 22 meters (72 feet). On Carson Ridge inMarin County, as well asHood Mountain inSonoma County, the species comprises a pygmy forest of trees which do not attain heights greater than 240–360 cm (7.9–11.8 ft) due to high mineral concentrations in theserpentine soil.[4]
One notable population occurs in the Cedar Mountain Ridge area of EasternAlameda County. According to Carl Wolf, who extensively studied the New World Cypress in the 1930s and 1940s, seed from the Cedar Mountain stand ofCupressus sargentii produced the most vigorous seedlings.
Like many of the New WorldCupressaceae, Sargent cypress usually reproduces with the aid of wildfire, which cause an opening of the cones and exposure of bare mineral soil for seedling germination, though occasionally seeds will fall and germinate without fire, though such seems to be the exception rather than the rule. It is often the case that many trees in a particular stand will all be the same age, so that a sort of stratification occurs of different colonies all of the same age. Sargent cypress can begin producing cones as early as five or six years of age.[5]
Hesperocyparis sargentii was scientifically described by the botanistWillis Linn Jepson in 1909 and given the nameCupressus sargentii.[3] He found thetype specimen in theMayacamas Mountains in northern California.[6] Jepson also identified avariety of the species, var.duttonii, in 1923, but this has not become widely accepted.[3] For almost 100 year the status of the species was not disturbed until in 2006 the first of several proposals to move it to,Callitropsis alongsideCallitropsis nootkatensis. Further research lead to two proposals to move it to a new genus for new world species of cypress,Neocupressus andHesperocyparis.[3] As of 2024[update]Hesperocyparis sargentii is considered to be the correct classification byPlants of the World Online,[3]World Flora Online,[7] and the USDANatural Resources Conservation Service PLANTS database.[8]
