Logging and Fire Hazards: Why does Logging Create Additional Fire Hazards

It seems to come up in any logging plan, that the purpose of logging is to reduce fire hazards. CGF has uncovered information about why logging in redwood forests can actually increase fire hazards, at least in the first few years after the harvest. The following is a handout prepared by Lennie Roberts that we distributed at a public hearing about the YMCA's Proposed Timber Harvest Plan at Camp Jones Gulch.


Commercial Timber Harvesting and Fire Hazards at Camp Jones Gulch

The NTMP (Nonindustrial Timber Management Plan) for Camp Jones Gulch proposes commercial logging in perpetuity. Up to 40% of the trees 18 inches and diameter will be harvested every 15-20 years. Old-growth redwood and Douglas fir trees in two groves are not proposed for logging, unless they are determined to be “hazards”. However, cutting of up to 20% of the second-growth trees within these areas is allowed by the Plan. The Plan can be amended in the future, without public comment.

Commercial Timber Harvesting will increase fire hazards

Redwood forests are dependent upon the cool, foggy coastal climate in the Santa Cruz Mountains. Mature redwood and Douglas fir trees create a canopy of continuous shade that discourages fire-prone shrubs, trees and other sun-preferring vegetation from growing. Summer fog drip replenishes water in the creeks, and maintains moist conditions that keep fire hazards low. In San Mateo County, up to half of the annual precipitation recorded in redwood forests comes from summer fog drip.

Cutting of the largest trees in a commercial timber harvest opens up the tree canopy and exposes the forest floor to direct sunlight. The resulting hotter, drier conditions on the forest floor increase the fire hazard. Logging debris and slash (tree branches, tops, and brush) from cutting of timber, up to two feet deep, is left on the forest floor, adding to the fire hazard. Increased sunlight encourages the growth of weedy and fire-prone species such as tan oak, California lilac (ceanothus), and broom. These fast growing shrubs and trees become “ladder fuels” which enable a fire to spread up into the canopy of the forest. As the forest recovers and the tree canopy grows back, the sun-preferring weedy species become shaded out and eventually die, adding to the fire hazard.

An additional hazard associated with the Camp Jones Gulch NTMP is the proposed use of herbicides on tan oaks. Tan oaks are not considered desirable in a commercially managed forest. They invade recently logged areas, and will re-sprout vigorously if cut. The NTMP proposes to use a method called “hack and squirt” in which herbicides are squirted into a cut in each tree trunk, killing the tree. However, unlike many other species, the leaves on dead tan oaks do not fall off. The leafy dead standing trees become virtual torches - one of the “ladder fuels” that the YMCA is concerned about.

Note: In its review of a 1976 Timber Harvest Plan for the Jones Gulch property, California Division of Forestry stated that the fire hazard will be increased for a period of 4 to 5 years rather than one or two years as the YMCA had predicted. In fact, the hazard is much greater than that due to the abundance of brushy shrubs and trees growing back after each timber harvest cycle. Yet, one of the YMCA’s stated purposes of this NTMP is to reduce fire hazards.

There are alternatives to Commercial Timber Harvesting

The YMCA should adopt and implement a strategic fire plan. This would include control of vegetation along Pescadero Creek Road, and the Camps’s ingress/egress road. Within 100 feet of the buildings in the developed area of the Camp, the YMCA should maintain 100 feet of defensible space required by State law. Within the next 200 feet, and other strategic locations such as ridge tops, the Camp should implement shaded fuel breaks. There are funding sources to assist landowners with fuel reduction, and there are potential partner organizations to implement fuel reduction programs.

Lennie Roberts, Legislative Advocate