Also called the water pine, the Oriental swamp cypress (Gylptostrobus pensilis) is the sole member of its genus. Native to China and neighboring portions of Vietnam, the trees show many similarities to their close relatives, the bald cypresses (Taxodium spp.).
Like bald cypresses, Oriental swamp cypresses commonly grow in low-lying, damp areas. They often grow best in flooded sites, including areas with up to 24 inches of water.
To cope with constantly flooded conditions, Oriental swamp cypresses often produce pneumatophores — roots that grow upward to access oxygen (often called “knees”) — just as their relatives do. However, the Oriental swamp cypress does not grow as quickly as its relatives do. These deciduous trees usually leaf out later in the year than their relatives do, and they shed their leaves later in the autumn.
Description
Oriental swamp cypresses are medium- to large-sized trees, which may reach 100 feet in height, although most specimens are less than 80 feet tall. However, specimens planted outside their native range usually remain less than 40 feet tall.
Oriental swamp cypresses are often the dominant species in the swampy habitats it calls home, and occasionally it forms pure stands. These trees are monoecious – individual plants bear both male and female flowers – and are pollinated via the wind. The trees deciduous leaves are arranged spirally around the branches, but they are twisted at the base, which makes them lie in twin horizontal splays. The inch-long cones open at maturity to release the seeds.
Cultivation and Use
Oriental swamp cypresses are planted widely for a variety of purposes. They are planted as ornamentals in Europe and North America, while some Chinese farmers plant these trees near rice paddies and agricultural areas to help stabilize the soil and reduce the rate of erosion.
Oriental cypress trees require full sun exposure, although they adapt readily to most soil types. However, as they are not drought tolerant, and are likely to die within 24 months when planted in dry soil, oriental swamp cypresses are not an ideal selection for most Californians.
Commercial Application and Harvest
The timber from Oriental swamp cypresses is highly valued for fence posts and similar applications, due to its insect and rot resistance. The fine-textured, aromatic wood is also suitable for finer work, and is used to construct musical instruments and furniture. The roots of these trees are exceptionally buoyant, so they are used in the construction of buoys and similar goods. Tannins from the bark are harvested for use as dyes.
Many locals believe Oriental swamp cypresses are lucky, so only those that have fallen over naturally are now milled into useable timber.
Status in the Wild
Unfortunately, the value of the timber has taken a toll on wild populations of the tree, and it has become extraordinarily rare in the wild – the IUCN Redlist recently upgraded the species to critically endangered, upon finding no wild specimens in China and only a few in Vietnam. (IUCN, 2011) Botanists estimate that over 250 individual, wild-growing trees exist, but very few of these – if any – continue to produce viable seeds. In addition to overharvest and illegal logging activities, habitat alteration – such as the draining of swamps – has also reduced natural populations.