GINGKO BILOBA

NIGHT OF THE GINKGO

By Oliver Sacks

 

Today in New York—November 13th—leaves are falling,

drifting, skittering everywhere. But there is one striking

exception: the fan-shaped leaves of the ginkgo are still

firmly attached to their branches, even though many of

them have turned a luminous gold. One sees why this

beautiful tree has been revered since ancient times.

 

Carefully preserved for millennia in the temple gardens of

China, ginkgoes are almost extinct in the wild, but they

have an extraordinary ability to survive the heat, the

snows, the hurricanes, the diesel fumes, and the other

charms of New York City, and there are thousands of

them here, mature ones bearing a hundred thousand

leaves or more—tough, heavy Mesozoic leaves such as

the dinosaurs ate. The ginkgo family has been around

since before the dinosaurs, and its only remaining

member, Ginkgo biloba, is a living fossil, basically

unchanged in two hundred million years.

 

While the leaves of the more modern angiosperms—

maples, oaks, beeches, what have you—are shed over a

period of weeks after turning dry and brown, the ginkgo,

a gymnosperm, drops its leaves all at once. The botanist

Peter Crane, in his book “Ginkgo,” writes that, in relation

to a very large ginkgo in Michigan, “for many years there

was a competition to guess the date on which the leaves

would fall.” In general, Crane says, it happens with “eerie

synchronicity,” and he quotes the poet Howard Nemerov:

 

Late in November, on a single night

Not even near to freezing, the ginkgo trees

That stand along the walk drop all their leaves

In one consent, and neither to rain nor to wind

But as though to time alone: the golden and green

Leaves litter the lawn today, that yesterday

Had spread aloft their fluttering fans of light.

Are the ginkgoes responding to some external signal, such as the change of temperature or light? Or to some internal, genetically programmed signal? No one knows what lies behind this synchronicity, but it is surely related to the antiquity of the ginkgo, which has evolved along a very different path from that of more modern trees.

 

Will it be November 20th, 25th, 30th? Whenever it is, each tree will have its own Night of the Ginkgo. Few people will see this—most of us will be asleep—but in the morning the ground beneath the ginkgo will be carpetedwith thousands of heavy, golden, fan-shaped leaves.