Vineyard No Dust Sign

This plastic sign warns drivers to slow down to prevent dust from settling on and injuring grapes. It was one of many posted in the vineyards at Stag’s Leap Wine Cellars in California’s Napa Valley in 1996 and 1997. Purchased at the Napa County Farm Supply store, the signs reminded drivers to slow down when in the vicinity of the area’s most valuable, prime crop: wine grapes.

Many modern vineyards are laid out in blocks with narrow roads running between them and around the perimeter. These unpaved roads allow small tractors, pick-up trucks, and specialized machinery used in vineyard maintenance and during harvest to maneuver close to the vineyard rows. Because dust is an enemy of grapes—dust can contain predators like mites that destroy grape leaves—vineyard managers post signs like this to implore drivers to slow down.