In the summer, trees are wonderful sources of shade. They grace the neighbourhood with their arching branches.
Do your children want to study plants? Study trees! Trees are amazing. They can move water and nutrients from root to branch and from leaf to trunk. In the chloroplasts, green chlorophyll helps trees make food. It traps light energy so that plants can turn water and carbon dioxide and light into carbohydrates. That’s tree food.
Study the ways in which water moves up the tree. As water evaporates from leaves, this pulls the remaining water up the tree. This is simple to demonstrate. Place a straw in water and suck gently on the straw to remove some of the water from the cup. The water rises in the straw. When you reduce the pressure or stop sucking altogether, the water moves down.
Water also moves up the tree due to capillary action. To learn about capillary action, place one end of a rolled up piece of paper towel into a glass that has an inch of water at the bottom. What happens to the paper towel? It gets wet. Water molecules naturally stick together, but sometimes they find it easier to move through a system of cells. If these cells are pointing up, that is the way the water goes. In the towel and in the tree, the water finds it easier to move through the tree cells from the roots.
Often people think of fallen logs as a dead tree, useless clutter on the forest floor. However, a fallen log is anything but dead. The tree itself may not be living and growing any more, but many other animals and plants are living on the nutrients it stored throughout its life. Fungi sprout from the bark, and networks of mycelia gradually break down the tree. Woodbugs and worms eat the tree as it decomposes, and whole food chains of spiders, beetles, and decomposer animals live in and under the tree. Moss and lichen sprout on the bark, and as the tree begins to rot even more, larger plants can grow on it and use it as a source of water and nutrients.
Look under a log and around the log to document the life that is there. Bring out your camera and take photos inside and outside the log. Create a three-dimensional log out of your photos as a project, or create a virtual tour of the life in a log by posting these photos online.
Image courtesy of chillal at Stock Exchange.