Abscission Day

The ginkgo leaves rotate as they descend:
Fan shapes, catching the early sun.
They have chosen this bright, cold day
And jump off the branches, one by one,
But in rapid succession -
Then two dozen nearly at once.
Some sail sideways, caught by the breeze.
Some tumble end over end but stabilize,
But most dive stem down, pivoting,
Paratroopers into the mass of fallen comrades.
One leaf flaps frantically on its node.
Others stay calm.
The tree at the end has led the charge -
Its landing completed by 10 a.m.
The drifts beneath it are greener
Than the yellow troopers released by other trees.
Did they jump,
Or did the tree push them off?