The San Joaquin-Sacramento River Delta is considered by local farmers to be the birthplace of integrated pest management, said Cathy Hemly of Green and Hemly farms on Randall Island.

"A group of pear growers, working with ag extension, came up with IPM," Hemly said.

Hemly shared the IPM history during a tour of the delta for the International Food Bloggers Conference (IFBC), held over the weekend in Sacramento.

Hemly said about 50 years ago, pear farmers were faced with growing pest resistance to the pesticide glutathione, which was used routinely to control coddling moth.

"Growers got together with a...