The grass will be greener on your side of the fence if you use a mulching lawn mower — or at least your lifestyle will be greener and more eco-conscious. And some types of mulching mowers are even more eco-friendly.

Mulching mowers, which might be more accurately called “leaving lawn mowers,” shred your grass clippings and evenly spread them back on the lawn. The alternative is bagging the clippings and composting them or sending them to the landfill.

Some cities and states ban grass clippings from landfills because clippings are too beneficial to waste in a landfill. They can provide about a quarter of a lawn’s fertilizer needs if left on the lawn, and provide water-conserving shade. They also help feed beneficial bacteria in the soil under the lawn.

Eco-friendly mulching options are relatively new, but most mulching mowers are larger and more powerful than simpler bagging mowers. Therefore, they use more energy. The most energy-efficient mowers, of course, are manual reel mowers. They automatically leave the clippings on the lawn, but are not technically mulching mowers.

The most powerful and most popular mulching mowers are self-propelled gas mowers, but they are noisy, dangerous and dirty. The typical self-propelled gas mower emits as much air pollution per hour as 11 cars, according to the Environmental Protection Agency. Here are two alternatives that perform as well as many self-propelled gas mowers, but leave a smaller environmental footprint.

Electric Mulching Mower

Electric mowers avoid some of the emissions of gas mowers (but keep in mind that most electricity is coal-powered, so electric mowers may not absolve you of all emissions-related guilt). However, corded mowers can be a hassle. My wife refuses to deal with the tangle of extension cords required to get past our trees and around our lawn with our corded lawn mower.

A solid alternative is the Toro E-Cycler mower, which uses a rechargeable battery. Toro promises up to 10,000 square feet of mowing power for each 16-hour charge.

An even better option would be the Bosch Rotak cordless lawnmower, which uses lithium-ion batteries that are easier to recycle, recharge faster and involve fewer emissions to produce than the more standard battery types. However, these European mowers are not available in the United States yet.

Propane Mulching Mowers

There also are ways to cut the emissions of gas-powered mowers. Honda’s full line of gas mowers are known for low emissions, but propane-powered mowers pollute even less. As noted, propane is a relatively eco-friendly fuel, and most propane is produced in the United States, so propane mowers arguably help move America move toward energy independence. Propane has no evaporative emissions or ozone-depleting hydrocarbons, and very low particulate emissions. Propane is not considered a groundwater or soil pollutant.

One popular option is the LEHR Eco LawnMower, which comes in both push and self-propelled models. The mower runs on the same small propane canisters that power many camping stoves, and the same amount of fuel lasts longer than comparable gasoline mowers.

Consider a battery- or propane-powered mulching lawnmower for the greenest way to keep a trim green lawn.