Six hundred and eighty four women and their hungry babies held the mass feed to mark World Breast-feeding Week on Saturday.
But the number fell short of the 1,130 women required to better last year's nurse-in, an event which made it into the Guinness Book of World Records.
However, the group was happy to have demolished a challenge by buxom counterparts in Australia, who could only muster 48 women a few days earlier.
"We still have our record," said Lyn Diana, one of the organizers, adding the event was held to promote breast-feeding, done by only an estimated one-third of American mothers.
Some good points
"The more we see people breastfeed in public, the more it will be reintegrated into the culture," she said.
She criticized hospitals for pushing women to use artificial baby formula, saying the manufacturers pay the hospitals to promote it rather than natural nursing.
Diana is adamant that new mothers should be weened off using artificial alternatives.
The event drew women from around California and several other states, gathering in a party atmosphere, at a Berkeley park, to the beat of an all-woman salsa group.
"It's good to bond with other breastfeeding mothers," said Tori Kopplemaa of San Jose.
"It's been a lifelong dream of mine to be part of a world record," said Rachel Camero of Sacramento, who brought her eight-month old son Lorenzo to take part.
Though disappointed by the result, she said it was important to promote breastfeeding.