The leaves are falling – so be it – Daily Press
Many insect species use leaf litter to overwinter, with moths and butterflies emerging in the spring as adults to feed birds and their young. Fallen leaves shelter small animals and invertebrates that feed larger animals, decompose organic matter and form rich soil. A thin layer of leaves won’t hurt the grass – if the coverage is more than 50%, the mower will chop them into smaller pieces to fall between the grass blades to decompose and nourish next year’s grass.
We, humans, and all animal life are completely dependent on the photosynthesis machinery of the green leaf. Using only sunlight, water and carbon dioxide, green leaves produce all the essential chemicals we need to support life. Carbon, oxygen and water combine to form carbohydrates from which proteins, lipids and DNA are produced. All of our food can be traced back to this process.
Soil organisms – large and small – will process the leaf into usable components. The largest are earthworms and nematodes, and the smallest are bacteria, algae and fungi. The dried leaves also contain water-soluble vitamins, minerals and hormones to nourish the developing roots of the mother tree and its siblings.
In many parts of the world, and certainly here in Tidewater Virginia, we enjoy a beautiful, vibrant display of fall colors – the brilliant red of the maples, the russet oaks, the golden yellow of the famous tulips, the purple of the dogwoods, and the tawny beech. the trees. These changes occur when days become shorter and trees get less sunlight. Chlorophyll breaks down, revealing colorful pigments that were hidden during the growing season. The best colors occur when the weather is dry, sunny and cool.
As the weather changes, massive chemical changes occur within the leaf. When chlorophyll decomposes and photosynthesis slows, nutrients and nitrogen are transported to the roots and trunk for winter storage. Fluids in the branches stop flowing to the leaves, a seal forms around the base of the leaves and they break off and fall to the ground.
The leaves of evergreen trees, such as pine, can survive the winter with a waxy coating and fluids in the cells that contain chemicals that fight freezing. The leaves of broadleaf trees have no such protection and freeze in winter, causing water to freeze within the tree’s trunk and branches. So trees shed leaves and convert much of the water inside the bark into sugars that act as a natural antifreeze.
As the leaves fade, their contents are recycled. Soil microbes convert them into water-soluble chemicals that are used by plant roots and the circulatory system of animals. Regular recycling of nutrients is crucial to us and the health of our planet.
Let them…leave the papers!
Helen Hamilton is a retired York County teacher.
