Eucommia ulmoides aka Eucommia

Eucommia ulmoides is a leaf-shedding tree from central and southern China. Gardeners call it the hardy rubber tree or Chinese rubber tree. It belongs to Eucommiaceae, and its genus has no other living species. People grow it widely for its bark's use in Chinese herbal medicine. NC State describes wild trees as threatened, without a formal conservation rank.

Garden trees reach 40–60 feet [12–18 m] in height. Their crowns spread 30–50 feet [9–15 m] across. RHS gives a narrower spread of 13–26 feet [4–8 m]. UConn notes that some trees spread wider than their height. Young trees have a pyramid shape, which becomes round and dense. Sources differ on growth speed, from slow to medium. Gray-brown bark forms ridges and grooves as the tree ages. Brown stems lack a true bud at their tips.

The simple leaves grow in an alternate pattern along each stem. They have oval shapes, pointed tips, and toothed edges. Their green surfaces shine, and older leaves develop wrinkles. Torn leaves reveal fine threads of rubbery latex between the halves. The leaves offer little fall color and may drop while green. Male and female flowers grow on separate trees in spring. Missouri Botanical Garden gives April as the flowering month. The small green-brown blooms add little show to the garden. Female trees bear flat, winged fruits called samaras from summer into fall. Each fruit holds one seed and has a notched tip.

Choose full sun, though Missouri Botanical Garden also allows part shade. The tree suits fertile soil that drains well and stays moist. It accepts clay, loam, sand, and chalk, across varied soil pH. Once established, it can cope with dry spells. Sources place it in USDA zones 4–7, with some caution for zone 4. RHS assigns H6 for UK gardens. Its broad crown suits lawns, parks, and streets where space allows. The shiny leaves provide its main display and help make good shade. Growers can raise new trees from seed or cuttings. Sources report few major pest or disease problems and low upkeep.

PFAF lists young leaves as edible but gives no preparation details. It reports no known hazards, rather than proof of safety. The bark has a long history of herbal use in China. PFAF discusses its use for high blood pressure and other conditions. The tree also yields gutta-percha, a rubber-like material used for electrical insulation. The reported yield does not support commercial rubber production. People have used its wood to make shoes with raised soles.