Chemistry with Richard Bleil
Welcome to fall, y’all. Personally, I’ve always preferred the term “autumn” as it somehow just sounds more appealing in my ears, but fall is appropriate. As I look out of my window, the leaves are all turning and once again falling from the trees, blanketing the ground beneath.
Today I read a meme basically asking people that they not rake up and bag their leaves. There are animals that will hibernate in those leaves and use them as cover for protection and warmth. And, yes, I do love the little animals. The other day I saw a garter snake on my driveway. She was so adorable, but certainly didn’t want to be handled as I went to try to pick her up and move her to safety as my lawn was being mowed. That’s okay, though.
But there is an ancient reason that you should not pick up leaves, that being alchemy. In modern vernacular, I’m talking about the law of conservation of matter. Matter is necessary to create those leaves. Yes, I understand cell division and all of that, and yes, the carbon, oxygen and even hydrogen in the new leaves can be derived from air (carbon dioxide and water). But what about the phosphorous? Nitrogen? Sulfur? Trace elements?
Every leaf requires matter to grow. It requires nutrients brought into the tree from the roots, and those same chemicals that make the leaves drop back to the ground when the leaves fall. When those same leaves are raked up and removed, so are the nutrients and chemicals that went into making them. Left in place, and mowed over in the fall, they quickly decay, and all of those chemicals and nutrients are returned to the soil. Otherwise, they’re gone to the landfill.
Yes, the nutrients can be replaced. Yes, you can spend extra money on fertilizer to replace the nutrients. That way, you not only get to put in the extra work of raking, bagging and removing, but you also get the joy of the extra work and expense of buying and spreading the fertilizer. A friend of mine is very proud of her lawn, and I’ll not speak badly of her as she puts in Herculean efforts to fertilize in the fall and spring, but she learned the hard way not to let her husband try. He just doesn’t put the care into the lawn that she does, and with the same fertilizer she uses to make the lawn beautiful, he caused stripes in the lawn and spots where too much fertilizer burned and killed the grass while other sections didn’t get enough.
The process of growth fascinated and confused ancient alchemists. They never published textbooks until they were all but gone, driven out by the beginning of modern chemistry. In those days, they decided to publish what they could as a way of immortalizing their works, gathering what they could to create at least a few books. And, of course, I have one, compiled by the alchemist Eirenaeus Philalethese in which a marvelous experiment is described in great detail on the growth of a plant. The alchemist carefully weighed the mass of the plant every day, including the pot and soil, and the mass of the water added each day. In the experiment, they proved that the plant violated the law of conservation of matter, but, of course, they neglected to consider that it was also absorbing carbon dioxide to create sugar.
Personally, I have an electric mulching mower for my lawn. I don’t remove the clippings after I mow, and I do mow over the leaves as it all fertilizes the ground. It doesn’t look great. If you like the look of a clean lawn with perfectly trimmed grass, this might not be the best approach for you, but my lawn does look nice and when I see the leaves, I stop to think about the chemical processes and habitats for critters. That, to me, makes it look far more beautiful in my eyes than it might look in the eyes of my irritated and uptight neighbors with the perfect lawns. And by putting less work into my lawn, I also have more time to enjoy being outside and doing fun things. So, yes, I’m advocating leaving the leaves when the leaves leave the trees. Try saying that five times fast. Of course, the choice is yours, but I’m looking forward to saving my back, saving on the amount of work I need to do, saving on the fertilizer I won’t need to buy and saving on the time I’ll have by not spreading fertilizer. But that’s just me.