Fall Color Report
Color creeps in like the fog on the first autumn mornings. Sunny days and cool nights are the recipe for those brilliant hues that paint the parks in October. Follow the fall in the Metroparks. You won't want to miss a day.
Take a Scenic Drive
Featured Trails for Fall Color
Follow the Towpath from Providence all the way to Farnsworth on this 8.3 mile historic path along the river. Trees along the trail are typical of floodplains and include cottonwood, sycamore, buckeye, basswood and walnut.
Oak Openings Preserve
All Purpose Trail
Take a relaxing long walk or a short bike ride on this 5.3 mile loop trail connecting Mallard Lake and Evergreen lake—two favorite destination spots inside the park.
Upland Woods Trail
The longest walking trail at Wildwood dips through winding topography in a forest dominated by oak, maple, cherry and sassafras. Two overlooks on the trail offer views of fern-covered slopes and lush ravines.
Why Leaves Change Colors
The timing of color changes and the onset of falling leaves is regulated by the calendar as nights become longer. As days grow shorter and nights grow longer and cooler, biochemical processes in the leaf begin the color changes. The following three factors influence autumn leaf color.
1. Leaf Pigments:
- Carotenoids: Produces yellow, orange, and brown colors (as found in carrots and bananas). Present in the leaf cells throughout the growing season.
- Anthocyanin: Produces reddish to purplish colors (as found in cranberries, blueberries, and strawberries). Most are produced in the autumn in response to bright light and excess plant sugars within the leaf cells.
- Chlorophyll: Gives leaves their basic green color, yet is a very strong pigment and overpowers the other pigments. It is necessary for photosynthesis---the chemical reaction that enables plants to use sunlight to manufacture sugars for food. During the growing season as leaves are serving as food factories for the tree, chlorophyll is continually being produced.
2. Length of Night
In early autumn, in response to the shortening days and declining intensity of sunlight, leaves begin the processes leading up to their fall. As night length increases, chlorophyll production slows down and then stops until all of it is destroyed. The veins that carry fluids into and out of the leaf gradually close off as a layer of cells forms at the base of each leaf. These clogged veins trap sugars in the leaf and promote production of anthocyanin. The pigments that are present in the leaf are then unmasked and show their colors. Once the separation layer is complete and the connecting tissues are sealed off, the leaf is ready to fall.
3. Weather Conditions
The amount and brilliance of the colors that develop in any season are related to weather conditions that occur before and during the time the chlorophyll in the leaves is dwindling. Temperature and moisture are the main influences.
Warm, sunny days and cool, (but not freezing) nights seems to bring about the most spectacular color displays. During these days, lots of sugars are produced in the leaf, but the cool nights and the gradual closing of veins going into the leaf prevent these sugars from moving out. These conditions – lots of sugar and light – spur production of the brilliant anthocyanin pigments, which tint reds, purples, and crimson. Because carotenoids are always present in leaves, the yellow and gold colors remain fairly constant from year to year.
The amount of moisture in the soil also affects autumn colors. Like the weather, soil moisture varies greatly from year to year. A late spring, or a severe summer drought, can delay the onset of fall color by a few weeks. A warm wet spring, favorable summer weather, and warm sunny fall days with cool nights should produce the most brilliant autumn colors.
Information adapted from: https://www.fs.usda.gov/visit/fall-colors/science-of-fall-colors
Leaf is palmate (resembling an open hand) compound with usually five leaflets. The margins are serrated.
Shiny leaf is simple and triangle shaped. Margins have rounded teeth that are slightly hooked and leaf stems are flattened.
Shiny leaf has many pointed tips with bristles.
Tree contains three different types of leaf shapes: unlobed, two-lobed and three-lobed. Unlobed leaves are oval shaped; two-lobed leaves contain one large lobe and a smaller side lobe that resembles a mitten; three-lobed leaves have a large central lobe and two smaller side lobes.
Leaf is palmately (resembling an open hand) divided into five pointed, primary lobes having a few large teeth. The top of the leaf is a medium green and the back is whiter in appearance.
Leaf has three to five palmate lobes and coarsely toothed edges, pointed tips and broad bases. Some hairs exist on the leaf, depending on its age.
Rectangular shaped leaf (resembles a cat face) has four lobes and tips as well as a flat top. Its edges are smooth.
Hairless leaf has rounded tips and three to five pairs of medium to deep lobes. The back of the leaf is a lighter green.