New Jersey is taking aim at gas-powered leaf blowers with a bill supporters hope will see action before the trees start shedding their leaves this fall. The bill, S-217, would ban some gas leaf blowers for most of the year, give credits of up to 50% to people who buy electric ones and let towns retain money they get from enforcing violations. The bill’s sponsor, Sen. Bob Smith (D-Middlesex), who chairs the Senate’s Environment and Energy committee, said it’s meant to cut down on air and noise pollution. “Gas-powered leaf blowers have for years been a scourge on the local environment. Not only …