Fall foliage: leaf season is here

There is no question about it; leaves are falling onto lawns, driveways and sidewalks, and most of us have raked or blew at least a couple of bags worth out of the way. On a brighter note, many towns have some form of fall foliage festivals on tap, as this region attracts viewers from near and far for the peak of the fall foliage season.

The mountains and valleys of the region carry a rich diversity of deciduous, or leaf-bearing, tree species, and each species contributes a different color to the brilliant patchwork of trees on a hillside.

Colors appear in leaves when nutrients are cut off from the leaves just before trees drop their leaves. The colors become apparent when chlorophyll (this gives leaves their green color) levels are reduced, and chemical compounds that are already present in the leaves become more visible. Compounds such as carotenes and xanthophylls give some leaves, such as birch, their bright yellow color while compounds such as anthocyanin make leaves such as maple leaves a fiery red. Anthocyanin is produced by the tree as chlorophyll levels drop.

The colorful ridgelines and valleys is a sign that autumn is here. It is a time for hunters to catch the early game seasons, a time for birdwatchers to see migrating raptors and waterfowl, and yes, a time to rake the leaves. Enjoy.