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Although the contemporary provenance of Ginkgo
biloba is East Asia—plentiful around temples—
the species grew in North America during the
Jurassic period, 180 million years ago.
The ginkgo is a quintessential urban tree. It is
tolerant of air pollution and poor soils as well
as the diseases and pests that have decimated
our most beloved forest and urban trees. In the
borough of Manhattan, more than 9 percent of
all trees are ginkgos. According to NYC Street
Tree Census data, Ginkgo biloba is also the 9th
most dominant street tree species citywide.
Before we consider one of the most controversial
features of the ginkgo, let's look at other defining
characteristics of the species. The golden fall color
of Ginkgo biloba is stunning. Equally dramatic
is the ginkgo's senescence, which Peter Crane,
author of Ginkgo: The Tree That Time Forgot,
writes is "the most synchronized leaf drop."
The specific epithet of the species, biloba, is a clue to
a reliable field mark: many of a ginkgo's fan-shaped
leaves have two lobes, with a notch at the apex
of variable depth. Not all of a ginkgo's leaves are
lobed, however. Peter Crane notes that ginkgo leaves
that emerge from long shoots later in the season
are generally lobed in contrast to the frequently
unlobed leaves that emerge from short shoots. >>
Ginkgo leaf with no central notch.
Spur shoot, aka short shoot: note no notches on leaves.
Deeply notched leaf. Double-deeply notched leaf! Leaf with notch of medium length.
