Glyptostrobus pensilis aka Chines Swamp Cypress

Glyptostrobus pensilis has two common names: Chinese swamp cypress and Chinese water pine. It belongs to Cupressaceae, the cypress family of conifers. It comes from southern China, Vietnam, and Laos. It grows by rivers, ponds, and swamps in warm climates. Wild trees are now scarce, though people still grow it. Useful Tropical Plants reports its 2013 status as Critically Endangered. Farming has destroyed much of the wetlands where it grows. Changes in water levels also threaten seed growth in Vietnam.

Sources give different sizes for trees grown in gardens. Missouri Botanical Garden gives 60–90 feet [18–27 metres] in height. It lists a spread of up to 60 feet [18 metres]. Oregon State gives about 50 feet [15 metres]. Trees sometimes reach 100 feet [30 metres]. Useful Tropical Plants gives a usual height near 33 feet [10 metres]. The crown starts shaped like a cone, then spreads with age. Thick flares, called buttresses, help support the trunk. The main branches spread out to the sides. Brown or grey bark splits into long, uneven strips. Trees in water may grow roots that stand upright. These roots have two names: pneumatophores and knees.

Oregon State says the tree is deciduous, shedding its leaves. Useful Tropical Plants calls it semi-evergreen, keeping some leaves. Leaves start light green and turn deep brown in autumn. They grow in spirals but twist into two flat rows. Missouri Botanical Garden gives January to March as the bloom period. The parts that form pollen and seeds add little garden show. Wind carries the pollen. Seed cones grow on stalks and look like pears. They turn from green to yellow-brown as they ripen. Ripe cones open and release small seeds with wings.

Plant this tree in a wet site with full sun. It can also grow in some light shade. Missouri Botanical Garden reports that it grows in standing water. The depth can reach 2 feet [0.6 metres]. Avoid dry soil, which cannot meet the tree’s water needs. That source lists USDA zones 7–11. Oregon State starts at zone 8. The tree grows at a moderate rate and needs moderate care. Missouri Botanical Garden reports no major insect or disease problems. It suits pond edges and wet sites in parks.

Its wide roots help hold riverbanks and rice-field walls. People also plant it to shield land from wind. People use its wood for buildings, bridges, and furniture. The roots float and have supplied corks and life-saving floats. Bark and cone scales yield tannins for dyes and tanning. Plants For A Future reports no known edible uses. It records past uses of shoots for fever and skin complaints. These records do not show that home treatment is safe. The supplied sources report no known hazards. This does not mean they have proved the tree safe.