— By Tom Koritansky, Lake Metroparks natural resource manager
As the days shorten and become colder, nature still has one last spectacular show to put on before taking a break for winter. In the coming weeks, the familiar shades of green cast upon the leaves of trees will be replaced by a palette of colors complete with vibrant yellows and oranges, striking shades of red and subtle browns. Deciduous trees lose their leaves during the fall in order to prepare themselves to survive the upcoming cold winter months.
The science behind leaf color change is quite fascinating. Fall is truly a remarkable time to visit the parks, take in some magnificent scenery and watch resident wildlife prepare for the upcoming winter. It is also a great time to appreciate the true complexity of this amazing process that contributes to such beautiful landscapes before the trees enter their winter slumber.
Leaves are an important organ in trees that serve as the location where food and nutrients are produced. Trees produce their own food through a process known as photosynthesis. Photosynthesis takes place within specialized cells called chloroplasts that contain chlorophyll giving leaves their green color and allowing energy from the sun to be absorbed. Energy from the sun is used in photosynthesis to transform water and carbon dioxide into sugars that trees use as their primary food source. Oxygen is also produced as a byproduct of photosynthesis and is released back into the atmosphere (trees are largely responsible for the oxygen present in the atmosphere). During the spring and summer when temperatures are warm, days are long and soil moisture is plentiful, trees actively undergo photosynthesis. When conditions can no longer support photosynthesis after summer ends, temperatures cool and day lengths shorten, trees must prepare to survive the upcoming cold winter months.
Deciduous trees enter senescence, or the period that leaves stop functioning, in response to changes in day length and temperature. Shorter days and cooler temperatures signal trees to stop producing auxin, a key plant growth hormone. One of the functions of auxin is to control a special layer of cells at the base of leaves known as the abscission layer. When auxin is produced during the growing season, cells in this layer are prevented from growing; however, when auxin production is stopped in the fall, the cells of the abscission layer grow and cutoff the flow of water and nutrients to the leaves.
Other pigments are also found in leaves during the growing season but are masked because of the green pigmentation from chlorophyll. After the abscission layer develops, chlorophyll breaks down and these other pigments become visible creating tapestries of color. Carotenes and xanthophyll cast leaves in hues of yellow and orange. Anthocyanin, produced during the late summer and fall, transforms leaves into vibrant shades of red and purple. The amount of anthocyanin produced depends on the amount of sunlight exposed to the leaves during senescence. Greater sun exposure produces more anthocyanin increasing the redness of leaves. Anthocyanin combined with carotene produces showy expressions of orange and crimson. If some chlorophyll remains in leaves after senescence with high amounts of anthocyanin, they will appear brown. Late into autumn once most of the leaves have fallen, these colorful pigments will decompose leaving behind only tannins that also appear brown.
The forests of Lake Metroparks offer visitors a great sample of this marvelous show produced by our trees. Visitors to forests rich in sugar and red maple like those at Girdled Road Reservation will certainly not be disappointed by the variety of color possible. Spectacular scenery at Indian Point Park, complete with some truly stunning large oaks, maples and hemlocks, provides a full array of color along a dramatic background overlooking the Grand River. Be sure to watch the weather this fall for just the right time to witness the full extent of fall color. Some of the best fall color is produced when sunlight is abundant and temperatures are low but not freezing throughout the fall. These conditions break down chlorophyll more rapidly and produce the greatest amount of anthocyanin.
Be sure to take a look at our favorite fall hikes to discover your Lake Metroparks in full autumn brilliance.
Chapin Forest Reservation
With a panoramic view of everything from Lake Erie to the Cleveland skyline, the view of fall colors is one of the best overlooks anywhere.
- Enter from State Route 306 (Chillicothe Road) and drive to the end of the parkway (pictured right). Lucky Stone Loop Trail (1.5 miles) begins at the cul de sac/Ledges picnic area and takes you to the highest elevations in the park.
- Enter from Hobart Road and access Arbor Lane Loop Trail from the parking lot. Hike this gravel trail until it intersects with Lucky Stone Loop; hike to the overlook and enjoy the panoramic view described above.
Lake Erie Bluffs
Enter through Lane Road or Clark Road.
Lake Erie Bluffs features the natural wonder of Lake Erie in Lake County’s front yard. In addition to the more than three miles of trails, a 50-foot coastal observation tower overlooks the lakeshore with multiple viewing platforms along a staircase that culminates in a deck featuring 360-degree views. The height and location of the tower provide visitors with a unique view of the lake and the surrounding woods, fields and wetlands, along with a variety of wildlife
Hogback Ridge Park
Enter from Emerson Road
Few areas of this park offer the viewing vistas of some of the other parks, but here you walk through the colors. From the start of the Hemlock Ridge Loop Trail to the finish, fall colors will surround and envelope you. Come on a sunny day when the yellow leaves are at peak color and everything in the forest takes on a yellow glow.
Hidden Valley Park
Enter from Klasen Road
Take the River Breeze Trail; this riverside trail has excellent views of the forested hillside on the opposite bank. The display of colors never ends along the entire half-mile trail.
Indian Point Park
Enter from the upper parking lot on Seeley Road
Hike one mile along Point Overlook Loop Trail to Lookout Ridge Scenic Trail, which will provide a spectacular view over the Grand River valley and the hillsides will be alive with colorful leaves.
Hell Hollow Wilderness Area
Enter from Leroy Center Road
Walk Beech Ridge Loop Trail (0.5 mile) to a stunning overlook of the Paine Creek valley, more than 200 feet below. From this unique view, the breathtaking beauty of the season stretches out before you.