A blaze of orange, yellow, or red against the deep blue autumn sky is one of the glories of this season. Usually the humidity has fallen off from the marine influence of summer, making the sky the deepest shade it can attain this close to sea level. It is the perfect foil for fall’s color parade. But I kind of like to look down, too.
In fall, carpets of colorful leaves may appear in just a matter of days, making the whole landscape glow. Some of the first to appear are those of the liquidambar (Liquidambar styraciflua). Their maple-shaped leaves are only a few inches across, but in profusion, they create a fantastic show. Ash species also add to the tapestry. Some of them turn a very bright yellow, while others shade from deep red into burgundy and nearly purple. Ginkgo (Ginkgo biloba) creates its own golden carpet. The fan-shaped leaves are particularly ornamental, whether on the tree or on the ground below. Not often planted on the West Coast, catalpa (Catalpa bignonioides) has very large ovate leaves. In spring and summer, the light green canopy creates a peaceful vault overhead, but in fall, those same leaves form a patchwork of yellow on the ground. Poplars and cottonwoods (Populus species) drop their golden fall foliage in one last hurrah. Many other deciduous trees and shrubs contribute to the serendipitous design, although a number of them need cooler conditions to perform at their peak.
Fallen leaves don’t retain their color for long once they let go of their hold on life, so admire them where they lie before picking up that rake (please, no gas-powered blowers). If possible, leave them where they fall to contribute to the mulch layer, but if you must remove them, don’t forget that they make excellent additions to your compost pile. Since many of these trees are pretty large, you can enjoy them in our public parks and along the streets-and leave the raking to our public servants.