Leaves!Text Box: When I was a child, I loved leaves. I would jump in them, bury myself and my dog, and lay for hours. In the spring, I love to see my yard bursting with vibrant greens...and in the summer I look at those leaves and think of how they are all going to come down. Well, that time has come. So, instead of unleashing a military operation on my yard, I decided to embrace the decent with a learning activity for the kids...now, this is one of those days, where I am teaching my kids, and learning LOTS myself! Text Box: Things we learned: Leaves are natural factories. It is like each leaf is its own solar panel collecting energy from the sun to turn water and carbon dioxide into glucose. This process is called “photosynthesis”, which literally means ‘putting together with light.’ A chemical called chlorophyll gives the plants their green color. In winter, there is not enough light for photosynthesis to happen, so the plant relies on the stored glucose to survive the winter. The leaves you see on the trees are really ALWAYS brown, red, or yellow, but because there is so much chlorophyll in the leaves during the summer the color is hidden. (that was the thing that fascinated me) The stem of leaves is like a channel for water to come into the leaves, and glucose to go out to the tree and be used to grow, or stored for winter. As summer ends, these stems become spongy and eventually it closes off the ‘veins’ to the leaves, which slows, and eventually stops the nutrients from getting to the leaves. As this stem dries out it becomes brittle and eventually the leaves turn back to their ‘natural’ colors because the chlorophyll is not being produced any more. These special cells are called ‘abscission’ (or separation layer). Trees turn different colors because of different chemical reactions that take place. For example, in red and purple leaves, that comes from anthocyanin, which is an antioxidant type of glucose that gets stuck in the leaves. Oak leaves (primarily what we have) turn brown because of tannin, which is actually a waste product left behind when the chlorophyll disappears! (this was also fascinating to me) The best place on earth to see fall foliage? The Eastern United States. Oh, ya, I happen to live there!! What causes the best displays? Dry summer (yup, we had that) and bright sunny days with temperatures in the 40s at night. (we’ve had that too this year) And the leaves this year seem to have really lasted around here. These make the colors bright, and if we had cloudy and warm night? Drab colors.

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Text Box: We learned stuff at this site: Www.sciencemadesimple.com/leaves