TREES ARE LIVING FOSSILS IN AN URBAN SETTING
was recently reminded that some plants and animals can be readily identified
by their smell. The tea olives in my yard, for example, smell delightful.
trees dropping their fruits, however, do not smell so pleasant. Fortunately
they are not in my yard.
trees are extinct in the wild, and no one knows their origin for sure.
Only one species exists, with a botanical history traced back to China.
has one of the longest fossil records among the higher plants, has no
wild representatives and yet prospers today in China and North America.
of individual trees being scattered throughout forests across the Chinese
countryside, the strange tree is known historically only from temple
gardens. Most in existence today have been planted.
of biodiversity is globally pervasive, mostly the result of short term
exploitation by humans through a lack of awareness or a failure to appreciate
our unwitting treatment of the ginkgo tree has resulted in its preservation.
One of the most mysterious plants ever to reach North America, the ginkgo
serves as a reminder that human intervention into nature's ways can
sometimes end positively.
may have been clinging to the last thread of existence, only to be saved
by human meddling.
single species of ginkgo exists today, the sole surviving member in
the entire family. To place the taxonomic unit known as a family in
perspective, all species of oak, chestnut and beech trees comprise a
is the lone survivor of a family of trees with a fossil record extending
back more than 230 million years.
tree has been called a "living fossil" because the only record
we have of its past in the wild is through fossils.
of their relationship to modern trees, the leaves of ginkgoes are broad
and flat like hardwoods. However, the ancestors of ginkgoes were more
closely related to conifers.
other plant, ginkgoes have their own biopersonality. The trees can reach
a height of more than 80 feet, and the fan-shaped leaves turn bright
yellow in autumn.
sexes are distinct, with a particular tree being either male or female.
Male ginkgoes are nice trees to have around.
ginkgoes are especially attractive in the fall, and only the smell of
their fruit detracts from their beauty.
unaware of being near a ginkgo tree with ripe fruit casts a suspicious
eye for unleashed dogs and begins to step cautiously.
of the ginkgo fruit has been described in more delicate terms as having
the odor of "rancid butter."
books simply say the female ginkgo has an "unpleasant smell."
But anyone encountering the yellowish, plumlike fruit in the fall will
quickly assign a distinctiveness to the tree that no other can match.
ginkgo trees disappear from the wild in China? They are wind-pollinated,
so their demise was not due to extinction of some rare insect that served
ginkgo an overused wood product of some ancient Oriental culture? Is
the disappearance of the once-widespread tree the result of natural
processes of competition with other tree species or a pervasive blight
or attack by a specialized predator or parasite?
point, which further increases the mystery of why the species would
disappear from the wild, is that ginkgoes are noted for their resistance
to fungus, herbaceous insects and industrial pollution.
the unpleasant smell of ginkgo fruit for a short time in autumn, the
tree is beautiful. No one knows why ginkgoes survived in the temple
grounds, certainly not because some order of monks enjoyed the smell,
but presumably a religious order collected and replanted seeds.
even greater mystery is why they disappeared from all other areas. Whatever
the case, ginkgoes are still here with us, despite their official ecological
disappearance centuries ago.
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