Autumn is progressing rapidly and the last two weeks have brought high winds for several days in a row – several times. The leaves’ abscission layers (where the petiole joins the twig) allow the leaves to part easily from the twigs and sail away in the wind.
Each species of tree tends to have its own schedule for losing its leaves. In northcentral Pennsylvania black and yellow birch vie with red and sugar maples for the earliest to shed their leaves. After that comes a rush of white ash, black cherry, cucumber-tree, black gum, black locust and a host of less common trees. Last are the tulip-poplar, silver maple, the aspens and apple as well as American beech and the various oaks. Some oak and beech trees, especially younger individuals, may retain their brown leaves for a long time – even until the new leaves begin to emerge in the spring.
In spite of the high winds, we’ve recently been able to enjoy the last of autumn’s show of foliage. All on trees that typically shed their leaves toward the end of fall –