Explorers Club

On October 17, 2009, the Explorers met for a beautiful—but chilly—hike amidst the autumn colors at the Englewood MetroPark.

The group started with a quick review of the leaf identification skills they worked on at their previous meeting, practicing on one of the stately sugar maples near the parking area. They then talked about the reasons behind the spectacular color changes seen at this time of year. The students recalled the role of the chemical chlorophyll in producing food and energy for the tree. This chemical is so prevalent in leaves during the spring and summer months that its green color masks all other colors that might be present in the leaves.

There are indeed other colors in the leaves, though, caused by other chemicals. In the fall chlorophyll production shuts down in the leaves, triggered by the shortening length of daylight, and once the chlorophyll disappears the other chemicals and colors take center stage.

One family of these chemicals is known as carotenoids. As the first part of the name suggests, these are responsible for giving carrots their orange color, and they also give bananas their yellow hue. In the fall, the brilliant golds and oranges of many trees owe their color to carotenoids.

Another class of chemicals present in many leaves are anthocyanins. These chemicals give different fruits and vegetables red and blue shades, and the combination of them in tree leaves gives rise to colors from red to purple.

As the group set off down the trail, they paused a moment to look at one type of leaf that they definitely did not want to touch. Poison ivy can take several different forms in the Ohio woods, from a free-standing plant to a vine climbing the trunks of trees to something resembling a shrub. The Explorers recalled the old saying if one is unsure of a plant's identity: "Leaves of three, let it be."

On the hike itself, the Explorers visited two waterfalls (Pattys Falls and Martindale Falls). At both, they noted the presence of layers of sedimentary rocks forming the cliffs down which the water plunges. At both spots, layers of harder types of rock cap, or lie on top of, a thick layer of softer rock. The softer rock weathers (gets worn down by water, wind, ice, and temperature changes) faster than the harder layers above. The harder layers stick out over the softer rock for awhile until their weight causes them to crack and fall. In this way, the rock is slowly weathered and eroded away, and the cliff and waterfall both slowly retreat upstream.

Other items of interest along the hike included various mushrooms, berries, and even a recently-shed snakeskin. The biggest highlight, of course, was the mid-hike snack!

To see photos from our 2009 fall hike, click on the gallery link below.

Gallery

For a map and other information about the Englewood MetroPark, click on the link below.

Englewood Metropark

For more information on the changing color of autumn leaves, click on the link below.

Fall Colors