Opinion: Farms should be the new new thing for Silicon Valley (By Liz Snyder and Hank Herrera; Special to the San Jose Mercury News)EXCERPT: Land is precious. It feeds us, sustains our wildlife, keeps floods at bay and gives our kids places to taste fresh food and be wild and free. Yet the bulldozers have continued to roll right down to the last remaining tracts of fertile land. The recent growth of farms and gardens in greater Silicon Valley is phenomenal. From Veggielution in East San Jose to Full Circle Farm in Sunnyvale to Dig Deep Farms in Oakland, urban farmers are eking out their vegetable dreams across the Bay Area. Acres of cultivated land, interest from families and schools, and support from cities and counties are at an all-time high.