WASHINGTON -- A staple of suburban lawn care would have to clean up its act under emission limits proposed today.

Engine-powered push mowers and riding mowers account for up to ten percent of summertime smog-forming emissions in some parts of the country.

The Environmental Protection Agency's reductions would probably be accomplished by adding catalytic converters that reduce pollution from exhaust.

The proposal effects engines under 50 horsepower. The action would cut smog-forming emissions from the engines by 35 percent.

The rule would take effect in 2011 for riding mowers and 2012 for push mowers. California already has enacted the rule.