Are you ready for a little melodramatic news framing? How about this: every time you mow your lawn, you’re taking thousands of lives, essentially making yourself a mass murderer. Over the top? Absolutely. Incorrect? Not really, at least according to researchers whose findings were published in the journal Ecological Solutions and Evidence.
Their study found that mowing significantly cuts down the number of insect communities living in your lawn. To help you figure out how much damage you’re doing to your lawn, the researchers even built a free online Insect Calculator that estimates how many bugs are living in a patch of grass and how many are likely to disappear after you decimate the lawn…assuming you live in Germany, Austria, or Switzerland, which are the only countries currently supported.
Researchers combined data collected between 2012 and 2023 from more than 475,000 arthropods sampled across Germany and Switzerland. Their analysis found that unmowed meadows support about 73 percent more arthropods than recently mowed ones, along with significantly more species diversity.
How Many Bugs Die When You Mow Your Lawn, According to Researchers
Some of the insects were straight up killed by mower blades. Others survive but lose their homes, breeding grounds, and food sources that made that grass worth living in. Researchers specify that mowing itself, and not the type of mower and how often you use it, is the single biggest factor behind the sudden decline in insect population, but they do admit that gentler equipment and less frequent mowing can mitigate some of the damage to insect populations.
If you care about the number of insects you’ve got crawling around in your backyard, you can just let your lawn grow out a little bit without going so far as to turn it into a jungle that’s more of a reflection of your own mental health than it is of your deep concern about insects. Leaving even a tiny portion of your lawn or a meadow unmowed can make a big difference, as the researchers’ sample calculations found that leaving just 30 percent of a 100-square-meter meadow unmowed increased the insect population from about 13,000 to more than 17,000.
If you were to start rotational mowing, where you mow different sections at different times, you’d essentially turn sections of your yard into insect refuges where they can run and hide while you mow another section.
Even if none of that insect-genocide stuff matters to you, the basic observation here is still fascinating: the calm, serene lawn you see out the window is teeming with life and much busier than it seems.