By now, everyone has seen the photos from the Napa and Sonoma fires of torched houses across the street from untouched grapevines. Irrigated fields, whether the vineyards in Napa or the orchards and fields of Terra Firma and other farms around us, rarely burn in wildfires.
Dry grass on the floor of an orchard or vineyard may catch fire, but irrigated trees and vines themselves rarely burn — the leaves are singed, and then wilt and fall off. In contrast, a wild pine or oak trees have evolved with fire. They have oily foliage and sap as well as lots of dead branches built up over the years that immediately catch fire and then burn like torches.
Open fields of irrigated vegetables or other crops will not burn at all unless they are completely dead and dried out. Fire will literally stop at the edge of a green field and burn around it. Compare this to an unirrigated hillside of dry grass, which will burn so fast it is hard to outrun the flames.
Everyone loves California’s scenic wild landscape, the Ansel Adams vistas of grass, oak and pine. But it’s not a safe place to build houses. And any place where it brushes up against communities — a park or a riparian corridor — is a potential conduit for fire.
Agriculture in California has historically provided a critical role as a fireproofing between the wildlands we love so much, and residential areas where most of us live and work. Unfortunately, much of our urban and suburban growth of the last twenty years has paved over farmland and pushed right to the edge of the wildlands.
During the drought, agriculture was the target of relentless criticism from all sides about the amount of water it uses. One of the frequent arguments leveled by critics was that much of California’s agricultural production is exported, providing “no benefit” to our state. This mindset continues to influence policymakers to date, for example in new draft rules governing groundwater use on farms.
Many, if not most, of the winegrapes produced in Napa and Sonoma Counties are exported out of California. The worldwide success of the region’s wines is a primary reason why so much of the area is still planted to grapes. In another scenario, suburban growth might have expanded to cover both valleys from end to end, as it has in so many other places around the San Francisco Bay. Had that happened, the destruction from the fires would have been absolutely catastrophic as the fires jumped from one subdivision to another without the buffer provided by acres and acres of irrigated grapevines.
Smokey Bear famously holds a shovel — the primary instrument for fighting wildfire. But a shovel is also historically the tool most used by irrigators in California’s farm fields. There are many lessons to be learned from this terrible natural disaster, but this one is pretty simple: Irrigated agriculture has a huge role in helping protect us from wildlife.