We are in a season named after leaves: Fall. When deciduous trees drop their leaves they are shutting down their systems for the winter. In warm climates native plants don’t do this, rather they shed leaves over a period of time, never turning off their ability to create food through photosynthesis. Evergreens also do this, providing shelter and food for animals no matter the weather. In cooler climates many trees go into semi-dormancy, kind of a half sleep.
They reduce the number of leaves on their branches so that their productivity reduces but doesn’t completely stop. In cold climates many trees become living works of art as their leaves turn colors before falling. Much has been made of the beautiful sight of bare branches in a winter garden. A traditional Fall activity is the raking and disposing of fallen leaves. Happy kids jumping into leaf piles. However, we need to stop thinking that bare is beautiful; at least, as far as the soil is concerned.
The disposal of fallen leaves should be made an environmental crime. Trees drop their leaves to protect and feed their roots, and all the microbes that aid and abet them. Those decaying leaves also protect and feed bulbs, shrubs and other overwintering plants. Ever notice how snow melts around leaves and fallen branches first? That is because they also produce warmth as they decompose, warming the soil to keep the microbes alive.
To remove fallen leaves is to take away the tree’s food, nutrition, its disease and pest control and ultimately its health. It would be as if you had stored up a cabin for the winter with healthy food and supplies, and someone came and took most of your supplies except junk food, took your blankets, your firewood and your vitamins and medicines. You’d probably survive until Spring, but you wouldn’t be very healthy, and you’d stay in a hospital and be treated with drugs to combat the illnesses and injuries you accumulated. Your health would be greatly weakened.
This is what leaf removal does for trees. People rake up the leaves in the Fall, then in the Spring buy fertilizer (usually chemical thanks to persuasive advertising), insecticides, foliar sprays and other junk that they don’t need, take time and effort and mess to apply, are often a human health hazard if inhaled or touched, and are expensive. None of this is necessary, if people would only do less work and stop interfering. If they would leave the leaves, plant companion plants around the trees along with natives, everyone would be healthier.
People rake leaves and dispose of them because the leaves come from specimen trees usually dotted around lawn areas. Lawns are unnatural. Fun, pretty, functional, but unnatural. Grass doesn’t like leaves on top because the leaves block the light. Exactly. A layer of leaves around the base of the tree will prevent invasive weeds and grasses from stealing rich topsoil.
Even in grove situations, or under fruit trees, people are determined to clear every leaf off the surface of the dirt. Notice I say dirt, not soil. The trees know what they are doing; they know what they need and dropped leaves and fruit are there on the ground for a purpose. They feed the soil and thus the tree.
What can be the compromise? Allow the space under your specimen trees to be cleared of grass up to and a little beyond the drip line of the tree; further would be better. When leaves fall, rake them all under the tree, being careful not to pile them up around the trunk. Plant all the shade-loving plants and bulbs that you’d like to within that space, but include members of a plant guild: a nitrogen-fixer, a groundcover, a deep tap root that mines the soil, a mulch plant, a pollinator, etc.
Children like to play under the trees? Afraid of creatures lurking in the leaves? Then leave a space for human interaction. Make a barrier with stones or decorative edging that circles a little more than the drip line of the tree, but then cuts back to the trunk to leave a large wedge shape. Leave the leaves and fruit within the barrier, and keep the wedge clear for sitting and playing.
Still too many leaves? In their natural settings deciduous trees produce leaves enough to cover their roots and also the space between trees, which protects the fungal passageways that connect the tree roots. With a specimen tree that isn’t happening. What to do? Compost! Build an inexpensive bin with wire or pallets and cram the leaves in. Each leaf is a vitamin pill for your garden. Go in with your leaf-burdoned neighbors on the rental of a shredder and shred everyone’s extra leaves. Mulch all your garden beds and your lawn with shredded leaves. They will break down faster, heat up more quickly in a compost heap and take up less space. Your soil will turn into rich, fragrant loam.
Stilltoo many leaves? Post ‘free clean leaves’ on Craigslist or on your community bulletin board. Gardeners crave leaves, and may even come out to rake them up for themselves.
Please, please don’t send your excess leaves to the landfill. The soil desperately needs those leaves and with them you won’t have to resort to chemical fertilizers, chemical sprays, high expenses and heavy labor in the Spring. You can instead spend the time watching your garden thrive.