Beginning today, members of the California Leafy Greens Handler Marketing Agreement can begin using a new service mark that certifies their membership in the program.

The mark, which can be used on bills of lading, indicates a handler's commitment to a set of good agricultural practices audited by the Sacramento-based agreement.

At the same time, the California Department of Food and Agriculture will begin certification audits.

Agreement members, which comprise nearly all packers of leafy greens within the state, will be required to use the mark beginning Sept. 1, says agreement chief executive officer Scott Horsfall.

Violations of the marketing agreement can result in a handler losing the right to use the service mark.

The voluntary leafy greens marketing agreement was formed in response to the E. coli outbreak that was linked to California spinach last year. The marketing agreement represents about 99 percent of the leafy greens industry in California.