Every fall people waste millions of man-hours and untold amounts of money throwing away leaves. For the life of me, I cannot understand why someone would burn or throw away something as valuable as leaves. Leaves contain nutrients and organic matter, which improves soil. Leaves act as mulch, and help to hold soil moisture and keep soil cool. People pay big bucks for fertilizers, mulches and soil conditioners at garden centers, while others throw away perfectly good foliage. Throwing away leaves is tantamount to throwing away money.
I know some folks are simply closet pyromaniacs. The fall is just a good excuse for them to burn something. You will know one of these flame fetish folks when you see one. These poor match-happy homeowners can be found leaning on a leaf rake any November Saturday gleefully watching a pile of leaves smolder as they smoke up the neighborhood and pollute the air.
Leaves are essential in the cycle of plant life. They literally consist of nutrients that trees mine from the soil. In a process called nutrient cycling, materials are removed from the soil, used by the tree and returned to the soil when tree parts decompose.
Trees use their roots to extract nutrients from the soil and manufacture leaves. These are used by the tree to produce food for the tree. They are discarded at the end of the summer. In nature the falling leaves are decomposed by insects and other soil organisms into nutrients and organic matter. This replenishes the soil in a brilliantly designed cycle of life.
Just the other day, a guy who knows that I am an arborist asked me what he could do or buy to improve his ailing mature oaks. It seems their health has been declining over the past few years. The trees are slowly falling apart, their roots are sticking up above the soil and a few have died. After asking him some questions, it did not take long to figure out that he had inadvertently killed his trees. The man has spent the last twenty years merrily raking up all the leaves around his trees into piles and burning them. The soil around his trees has been depleted and the trees are starving. Their roots are cooking in the summer time under the bare soil and moisture evaporates quickly before the roots can take it up. The fact is he has nearly killed all of his trees by robbing them of nutrients and destroying his soil.
The sad thing is that he had to work to do it. He spent hours of his life that he will never get back working hard to get up all those despised leaves. What did he accomplish? He accomplished nothing other than killing his beloved trees.
Trees need cool, moist, nutrient-rich, well-drained soil to remain healthy over the long term. A layer of leaves over a tree’s root zone cools the soil, holds in moisture, provides nutrients and improves the soil. Leaves are the key to keeping landscape trees healthy. Use your leaves as mulch under your trees and please do not throw away the life of your soil and your trees.