How Green is Your Lawn, Really?
This is not going to be an article about artificial fertilizers, pesticides, herbicides, or any other harmful chemical commonly in use to make gardens pretty. I’m sure most people are aware of the collateral damage to wildlife and human health resulting from overuse of these products.
You don’t need me to tell you that artificial fertilizers in particular come with a hefty carbon footprint, and that all of these things end up poisoning groundwater in their own, special way. Heck, the modern environmental movement began with Rachel Carson’s legendary screed, Silent Spring, about just this issue.
No, let’s look at something less obvious. Do you drive a lot? Gas prices being what they are these days, you don’t even have to be environmentally-conscious to limit your mileage where possible. For example, I doubt anyone but travelling salespeople take a 360-mile road trip every weekend. Would it surprise you if I told you your weekend at home gardening was just as damaging?
SafeLawns.org quotes an EPA estimate that running an average gas-powered lawnmower for one hour releases more than four pounds of carbon dioxide, two pounds of carbon monoxide and the better part of a pound in various “volatile organic compounds.” The same Fact Sheet also tells us that a staggering ten percent of air pollution in the United States comes from gas-powered lawn equipment, like lawnmoweres, weed whackers and chainsaws.
Ten percent! How is that possible?
When I came across this rather astonishing fact, however, it jogged something. I’ve spent a little time living in Asia, including Thailand. Thai roadways include an incredible array of motorized transport, especially small-engine vehicles. Tuk-tuks, motorbikes, scooters and the like are cheap to buy and maintain. They’re the vehicle of choice for couriers and even taxi services.
Many, if not most of these of these vehicles, have traditionally utilized a two-stroke engine system. Compared to the four-stroke system found in all larger vehicles, two-stroke engines are remarkably inefficient. Burning a combination of gasoline and motor oil in a set ratio, two-strokes don’t burn their fuel as effectively, releasing less energy and, ultimately, producing more pollutants — compared to a four-stroke, twice as much of certain pollution emissions for the same amount of gasoline burned.
The Thai government has been working hard to get two-stroke engines off the road for a decade, using a combination of regulation and trade-in incentives. You know what other gas-powered machine frequently uses a two-stroke engine system? That’s right, your lawnmower. Now it all starts to become clear.
The Thai motorbikes illustrate an important point. By and large as gas has become more expensive, people have become a little less wasteful of it. But small two-stroke engines can be cheap on gas and expensive to the environment. In effect, they’re using less than their share of gas, but more than their share of pollution per quantity of gas. Efficiency matters! Don’t assume that because you are spending less at the pump, you’ve automatically become more eco-friendly.
The EPA has been phasing in new emission standards with respect to small gasoline-powered equipment, but there are likely many 20-year-old chainsaws and mowers still in use today, so changing production practices now won’t have a large effect on these emission sources immediately. If you have an older mower, they recommend minimizing your mow time and other mitigating measures to cut back on your emissions.
But frankly, if you have an old mower that spews out the equivalent of a weekend trip through wine country every time you cut your grass, I’d just recommend getting a new one. That’s just too big of an environmental cost for something as simple as mowing your lawn. Shell out the cash for a better mower. Chip in with friends and timeshare if need be.
And if you’re buying anyway, well, let me show you my lawnmower. I can’t tell you how much I enjoy not filling it up with either oil or gasoline. Go electric, or go old school and grab one that’s human-powered. Your yard and your lungs will thank you.
Photo credit: ThinkStock