From my observations, last Oct. 14 was the overall fall color peak for all of the Twin Cities, and also for the St. Cloud area to St. Peter, Northfield and into western Wisconsin. In 2013, the peak hit Oct. 13. This year’s peak should be close to these dates for the trees, shrubs and woody vines that provide the spectacle.

This is the time of the colorful woodlands. There may not be an illuminated woods where you live but all throughout Minnesota and the Upper Midwest, during this second week in October, there are illuminated trees and pockets with fall colors. The leaves of wild grapevines, hackberry trees and some willows are sunny yellow. Those leaves of bigtooth aspens and eastern cottonwoods are golden-yellow, while red oaks are displaying deep reds, and sugar maples display burnt-orange and brilliant red foliage. There also is bright reds on sumac shrubs and Virginia creeper vines.

In autumn, the leaves stop their food-making process because of less daylight and cooler temperatures. The chlorophyll breaks down and the green color disappears. Two underlying pigments, xanthophyll and carotene, are unmasked, leaving yellow and orange.

Some of my favorite drives are the Minnesota Landscape Arboretum; Highway 7 from Hopkins to St. Bonifacius; the many roadways around Lake Minnetonka; along the St. Croix River between Taylors Falls and Stillwater; and through Northfield into Faribault.

 

Jim Gilbert’s Nature Notes are heard on WCCO Radio at 7:15 a.m. Sundays. His observations have been part of the Minnesota Weatherguide Environment Calendars since 1977, and he is the author of five books on nature in Minnesota.