Did you know that 1 hour of cutting grass is equal to a 100-mile automobile ride? Really. According to a 2001 study published in the June issue of Environmental Science & Technology, Swedish scientists discovered that a 4 HP lawn mower emitted the same amount of PAH (Polycyclic Aromatic Hydrocarbons; a class of compounds that are suspected carcinogens) as a 93 mile ride in a modern automobile.

How can this be?

You may be wondering how lawn mower emissions can be worse than car or truck emissions. The problem lies in the fact that lawn mowers emissions aren't regulated and therefore do not have any type of controls, such as a catalytic converter, installed. This means that small engines (including lawn mowers, weed trimmers, chainsaws, leaf blowers) emit large amounts of carbon monoxide, volatile organic compounds as well as nitrogen oxides that all contribute to smog and pollution. The study goes on to state that the installation of a catalytic converter onto a lawn mower would reduce the levels of pollution by 80% (4000ug down to 800ug).

So what can I do about this?

Unfortunately modern lawn mowers still don't have catalytic converters installed but there are a few things you can do to reduce hydrocarbon emissions and still get the lawn mowed. Here are some suggestions how you can help reduce your lawn-mowing carbon footprint.

1. Switch Mowers – by far the best option would be to ditch your current gas-guzzling lawn mower for a reel mower. These mowers are the modern day ancestors of the lawn mowers your parents and grandparents used to use. While not a lot has changed in the design of reel mowers, the construction of the real mowers has improved to use rust-resistant coatings and blades that hold their edge better. If you don't like the thought of a reel mower, you could switch to an electric mower. Modern electric mowers have high capacity Lithium Ion batteries that allow them to hold a charge for a decent sized (1 acre or less) lawn and are quieter and easier to start than gas powered mowers. If you absolutely have to have a gas powered mower (boy, you're stubborn) you can get a modern push mower. If you're lawn mower is older than 10 years old then a modern lawnmower will be more efficient (increases in engine efficiency and propel design) saving you money and saving the environment pollution.

2. Mow less often – even if you can't afford a new mower (but reel mowers are cheap!) you can still reduce your emissions by mowing less often. I know that lawns are a reflection on your masculinity and a lot of pride goes into lawn care, but a lawn can be well maintained at a height of 3-4 inches by mowing once a week. The lawn will be healthier and you'll have less work to do, not to mention saving money on the gas.

3. Don't Mow at All – I'm not suggesting that you just let your lawn go to become whatever jungle it turns out to be (there are usually codes about that) but with some thoughtful planning you can create an enjoyable landscape that is both biodiverse and beautiful. Consider planting some local perennials and shrubs to cut down or eliminate all together the amount of lawn you have (and therefore have to mow). Putting down a thick layer of mulch each year will reduce or even eliminate the amount of weeding required. One day of work is way better than a whole summer's worth.

While some of these of suggestions might not be for you, anything you do will help to reduce the emissions you make when maintaining your lawn. Don't forget that it's not just your lawn mower that produces these emissions. Consider limiting the amount of weed trimming, leaf blowing, and tree cutting you do as well. Every little bit counts!