Building permanent firelanes is usually done with heavy equipment, to include bulldozer tractors with a blade or farm tractors with a disk. Bulldozers are a must for clearing new lanes where tree and stump removal is necessary. Other implements like mulchers and chippers can be used and mechanical spreaders for fertilization and seeding for establishing grass are very handy.
Firelanes are installed with the intent to minimize wildfire spread to other forests and to areas where structures are being protected. Firelanes should be located perpendicular to the prevailing wind and on the windward side of the area to be protected. Use firelanes in conjunction with existing barriers such as roads, cultivated fields, pastures, skid-trails and utility rights-of-way to limit firebreak construction and the expense involved. Natural barriers such as streams, lakes, ponds and rock cliffs should always be considered as part of planning the firelane construction.
For personal property protection landowners should establish firelanes along their property lines and parallel to public roads (a major source for initial fire starts). Remember to include existing woods roads when planning a firelane by widening it to create a permanent brake. Most state forestry departments will assist you with recommendations on establishing new firelanes if you call the local forest ranger headquarters.
Constructing a Permanent FireLane
Permanent firelanes should be at least 10 feet wide and maintained year-round by either disking to expose fresh mineral soil, especially prior to wildfire season, or bush hogging to maintain grasses less than 3 inches in height year-round.
Water diversions or bars should be created on sloping land. On flat terrain, ditches are needed on both sides of the firelane and should be diverted at every opportunity. The maximum grade of firelanes should not exceed 10 percent and water bars are purposely placed to minimize erosion. Percent of slope will determine spacing and dimensions of the water bars. Typically, water bars are 12 - 18 inches high and installed at a 30-degree angle down slope so water is diverted into forested areas. Fertilizing and seeding with species with dense deep root systems can further stabilize firelanes.
The spacing of diversions should be based on the length of the firelane as determined by the percent of slope of the terrain: if the percent slope of the terrain is 3%, then the lane should have a diversion every 200 feet; if 5% every 135 feet; 10% then 80 feet.
Stabilizing permanent firelanes is a must. Lanes should be kept disked, or preferably maintained with grass cover to prevent soil erosion. Consider using legumes, small grains, or other native grasses and remember to lime and fertilize when seeding. Scout your lanes and remove all burnable materials in early spring and early fall.
Other Considerations
- Mow or graze vegetative firelanes to limit excess litter and to control weeds. As I have mentioned, seasonally inspect all firelanes for woody materials.
- Reduce the forest fuel layers on both sides of the firelane to remove “ladder” fuels or flammable vegetation that connects to upper layers. Doing so prevents high canopy fires that can blow over the firelane. Also, thin the overstory stand to reduce the potential of a crown fire "jumping" the firelane.
- Design and layout should include multiple uses of the firelane. Typical firelanes also serve as access roads, walking trails and wildlife corridors.
- Comply with applicable federal, state and local laws and regulations during the installation, operation and maintenance of any permanent firelane.
