Ariel view of a home with the three wildfire buffer zones marked, like rings around the house. Zone 1 is the area within 30 feet of the structure itself. Zone 2 goes from 30 to 100 feet from the home. Zone 3 is the area from 100 feet to the edge of the property. 
Zone 3 is the first line of defense against wildfires. Remove all dead plants and trees from this area. Trim and space out tree and shrubs so they are least 10 feet apart, including branches. 
Zone 2 requires additional maintenance of vegetation. Regularly prune all trees and shrubs up to 10 feet from the ground. Leave 30 feet between clusters of trees, or 20 feet between individual tress. Keep grass to a maximum height of 4 inches. Move any combustible items, like sheds, trailers and benches, to Zone 3. If you can’t move something, clear the area around it so there is no direct path of combustible materials between it and the building. 
Zone 1 is the last line of defense. Keep this area free of dry or dead vegetation, like leaves, pine needles and brush. Use noncombustible landscaping materials, like gravel or rock. Be selective about the vegetation planted closest to the building. Certain annuals and perennials are good choices because of their high moisture content.