Ginkgo or the Maidenhair Tree.
Division Ginkgophyta > Order Ginkgoales > Family Ginkgoaceae.
Ginkgophyta is a group of ancient plants originally with about 10 genera but only one survives today.
Ginkgo biloba, a native of China, is the sole species and is sometimes referred to as a living fossil.
Its close relatives date back to over 200 million years.
Young trees are triangular with well spaced branches but become denser over time.
They are deciduous with the leaves turning a deep yellow before they drop.
Leaves are borne on either ordinary, long branches or on short shoots.
The short shoots are only a cm or two long with a cluster of up to 6 leaves.
The longer branches have single, more widely spaced, alternate leaves.
These leaves, on long petioles, are fan-shaped with blunt teeth along the distal margin.
Leaves on short shoots are usually entire but those on long branches have a deep notch giving a bilobed appearance.
Each leaf has 2 veins at the base which fork repeatedly until they reach the margins.
Ginkgo trees are either male or female and can take 10 to 20 years before they mature.
Male trees have cones with sporophylls bearing the sporangia which produce masses of pollen.
Female trees have no cones just a stalk with 2 naked ovules.
Seeds are about 2 cm with yellow pulp around a hard seed.
J.F.
