The bill, which County Executive Steve Levy pledged to sign, includes a maximum fine of $1,000. County property was excluded from the bill, Levy spokesman Mark Smith said, because fertilizer is only used on golf courses, at the county farm and at public works projects where sodding is necessary.

Smith said the county’s four golf courses and farm don’t ban fertilizer use during specific dates, but have a policy of “minimizing the use and using best practices.”

Carrie Meek Gallagher, the county’s environment and energy commissioner, said the law was designed primarily to stop commercial landscapers from using too much fertilizer. But individual homeowners and private golf courses are also covered by its provisions.

The bill also requires stores that sell fertilizer to post signs and informational brochures regarding fertilizer use within 10 feet of fertilizer display areas.

Asked by Legis. Ed Romaine (R-Center Moriches) how the county plans to verify fertilizer complaints, Gallagher said it would use carbon-dating to test the soil to determine the amount of fertilizer in the ground and for how long it was there.