Ginkgo | Description, Natural History, & Uses - Encyclopedia Britannica

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Physical description

ginkgo leaves
ginkgo leavesThe leathery fan-shaped leaves of a ginkgo tree (Ginkgo biloba), a gymnosperm.(more)

A ginkgo tree is pyramidal in shape, with a columnar, sparingly branched trunk up to 30 metres (100 feet) tall and 2.5 metres (8 feet) in diameter. The fissured bark is grayish, deeply furrowed on older trees, and has a corky texture. The light-coloured wood, soft and weak, has little economic value. Fan-shaped ginkgo leaves resemble the leaflets of the maidenhair fern and are borne on short, spurlike but greatly thickened shoots. The leathery leaves are up to 8 cm (3 inches) long and are sometimes twice as broad. Two parallel veins enter each blade from the point of attachment of the long leafstalk and fork repeatedly toward the leaf edges. Most leaves are divided into two lobes by a central notch. Dull gray-green to yellow-green in summer, they turn golden yellow in autumn, remaining on the tree until late in the season, and then fall rapidly.

Spreading oak tree in summer. (green, leaves, deciduous, shade) Britannica Quiz Trees: Giants Holding the Sky
ginkgo seeds
ginkgo seedsGinkgo seeds (Ginkgo biloba) have a malodourous fleshy covering.(more)

Microsporangia (pollen-forming structures) and female ovules are borne on separate trees. Pollen grains are carried to the female trees by the wind. Megasporangiate (female) trees bear paired ovules, which, when fertilized, develop into yellowish plumlike seeds about 2.5 cm (1 inch) long, consisting of a large inner nutlike portion surrounded by a fleshy outer covering.

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