Terry L. Ettinger Horticulture Consulting Services
Meeting The Needs Of Today With A Vision For The Future
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Leaves Aren't Trash
It's About Light and Water
Did you know that the maple syrup, corn syrup and sugar in your kitchen is actually condensed and/or dehydrated plant food?
That’s right! All green plants make their food through the process of photosynthesis. A simplified explanation of photosynthesis is that the physical energy from sunlight drives the chemical binding of six molecules of water and six molecules of carbon dioxide to produce one molecule of sugar (that's plant food, remember) plus six molecules of oxygen.
Is this bringing back nightmares of your high school science class? I hope not, because here comes the explanation for why it can be so hard to get grass to grow under the trees in your yard.
As sunlight passes through the trees in your yard, almost all of the photosynthetically active radiation (those
wavelengths of light energy that drive photosynthesis) is absorbed by their leaves. While this is good for the trees,
it’s bad for the grass under the trees. This is because there isn’t enough
light energy left to drive photosynthesis within the grass
blades by the time sunlight reaches the ground. The result is that grass plants under many trees, quite literally, starve
to death because there are not enough simple sugars being made
within their leaf blades (photo at left, above).
Adding insult to injury, the leaves of many trees - like those of the wildly popular `Crimson King’ Norway maple, deflect rainfall toward the `dripline,’ just like the shingles on a roof. That’s why after a relatively heavy summer shower, the soil under many large trees often remains completely dry. Ultimately, this lack of light and water prevents grass from growing, resulting in bare spots that you reseed over, and over, and over.
So, what does any of this have to do with the leaves dropping from your trees?
The point is that it’s always going to be a struggle to grow a nice lawn under the trees in your yard because their leaves prevent sunlight from reaching the ground. So why bother?
Now, I doubt that I’ll convince you to stop trying to grow grass where it’s simply not going to grow well. But, at least let me offer you some options for managing your tree's leaves by clicking on the links at right.