Bay senior foodies listening to the siren call of California agriculture should get out their gloves and head to your nearest U-Pick farm. The biggest concentration is 60 miles west of the City around Brentwood. But there are pick-it-yourself operations all the way down to Santa Cruz. The state’s cornucopia of stone fruits is ripening now –sweetly juicy peaches, nectarines and plums for starters. The cost at $1 to $3 per pound is usually less than at farmer’s markets. You can shop around for farms here or take the advice of the Chronicle. The weather can be chilly and foggy or scorching, so dress accordingly. The Geezer’s favorite sight last year was a field of corn being picked by Indian American women in brilliantly colored saris. Do what I didn’t do and bring your camera.