Fred Ross, a California labor organizer, spoke yesterday at Andover Hall in the Divinity School on the efforts of migrant farm workers to organize an effective union.

Ross said many Americans believe the battle to improve the farm workers' plight ended in 1975, with the passage of a California law allowing the UFW to organize farm workers and to hold free elections to determine union representation. "The struggle is not over," he said, adding that large farm owners still sometimes use armed guards to intimidate picketing union members.

Ross said the current law allowing the UFW to unionize workers is not sufficient to prevent a reversal of recent union gains. Only boycotts and continuous political pressure will allow the UFW to continue to be effective, he said.

The union will also try to organize inner city residents into a "poor people's union," setting up service centers to help them "deal with the welfare bureaucracy, medical problems and educational assistance," he said.

The job of organizing such a poor people's union will take several years, Ross said. In the meantime the union will try to extend its representation to farm workers on the East Coast, he added.

Ross recruited Cesar Chavez, the present leader of the union, from the barrios of San Jose in 1953.