1151-2815P-MTDC: Danger Tree Mitigation Guidelines for Managers page02

Table of Contents

Back | Next | Cover Page

Danger Tree Mitigation Guidelines for Managers

Introduction

Wildland fire safety awareness has brought about changes that have reduced injuries and fatalities. Safety awareness about danger trees is needed to help protect firefighters on incidents, employees in the field, and visitors on public lands. For example, the mountain pine beetle epidemic in the West is increasing the number of dead and dying trees on public lands (figure 1) and raises the risk for anyone in infested areas.

Marking and restricting access to areas where danger trees are located (a technique referred to as avoidance) can sometimes work. In other areas, removing danger trees is the appropriate decision, but it involves significant risk.

This report provides information to help managers evaluate three common methods of mitigating danger trees (blasting, mechanical felling, and manual felling with chain saws). Selecting a mitigation method requires careful analysis of the hazards associated with each method. After this analysis, managers can focus on logistical issues, expected production rates, and estimated costs. The cost estimates presented in this report are based on information provided (as of 2010) by U.S. Department of Agriculture, Forest Service employees, Forest Service contractors, and private industry.

Image of tubular masses of resin, also called pitch tubes, on the bark of a tree. The text "Pitch tube" is at the end of an arrow that is pointing to the pitch tube.
Figure 1—Tubular masses of resin (pitch tubes) on the bark of this tree indicate a mountain
pine beetle infestation.

Useful Terms and Definitions

Forest Service employees traditionally use the term "hazard tree" rather than danger tree. In this report, the U.S. Department of Labor, Occupational Safety and Health Administration (OSHA) term "danger tree" is used and has the same meaning as hazard tree.

Collateral Duties: Secondary work duties that are assigned in addition to an employee's primary work duties.

Danger Tree (or Hazard Tree): A standing tree that presents a hazard to employees due to conditions such as, but not limited to, deterioration or physical damage to the root system, trunk, stem or limbs, and the direction and lean of the tree.

—Occupational Safety and Health Standards, Title 29 of the Code of Federal Regulations (CFR) Part 1910.266(c)

Any tree or its parts that will fail because of a defect and cause injury or death to people. —"Field Guide for Danger Tree Identification and Response" (2008 edition), Forest Service, Pacific Northwest Region

Danger Tree Mitigation: Elimination or controlled avoidance of the dangers associated with a danger tree.

Diameter at breast height (d.b.h.): The average outside bark diameter of a standing tree when it is measured at breast height (4.5 feet above the forest floor on the uphill side of the tree).

Force Account Work: Work activities performed by permanent or temporary Forest Service employees rather than by outside labor.

Labor Intensive Service Contract (LISC): Contracts for on-the-ground services requiring extensive hand labor including, but not limited to, tree planting, tree thinning, tree pruning, cone collection, and other forestry-related services.

Qualified Person: A person who has knowledge, training, and experience in identifying danger trees, their potential failure zones, and measures to eliminate the danger.

—"Field Guide for Danger Tree Identification and Response" (2008 edition), Forest Service, Pacific Northwest Region

Solid Biofuel: Commercial timber fuel product derived from logging debris (also referred to as biomass).

Stand Density: Number of trees (stems) per acre.

Stewardship Contract: A written agreement that can help achieve land management goals while meeting local and rural community needs. This type of contract focuses on the "end result" ecosystem benefits and outcomes rather than on what is removed from the land.

Additional information is available at http://www.fs.fed.us/fstoday/091106/03.0About_Us/stewardship_brochure.pdf.

Tree Complexity: According to the National Wildfire Coordinating Group's Hazard Tree and Tree Felling (HTTF) Task Group, the elements of complexity include:

Felling Concerns—Amount/condition of material, size, bind(s), stability, defect, overhead and surrounding hazards, and potential for tree to hang up on other trees.
Environment—Slope, weather, and condition of ground for footing.
Secured felling/bucking area—Area that must be established, maintained, and restricted throughout felling operations.
Equipment—Equipment available, needed, and used, and its condition.
Human Factors—Assessment of risk, physical condition, individual experience, confidence, attitude, judgment, and ability to communicate.

Top

Back | Next | Cover Page




T&D > T&D Pubs > Danger Tree Mitigation Guidelines for Managers Table of Contents Back \| Next \| Cover Page Danger Tree Mitigation Guidelines for Managers Introduction Wildland fire safety awareness has brought about changes that have reduced injuries and fatalities. Safety awareness about danger trees is needed to help protect firefighters on incidents, employees in the field, and visitors on public lands. For example, the mountain pine beetle epidemic in the West is increasing the number of dead and dying trees on public lands (figure 1) and raises the risk for anyone in infested areas. Marking and restricting access to areas where danger trees are located (a technique referred to as avoidance) can sometimes work. In other areas, removing danger trees is the appropriate decision, but it involves significant risk. This report provides information to help managers evaluate three common methods of mitigating danger trees (blasting, mechanical felling, and manual felling with chain saws). Selecting a mitigation method requires careful analysis of the hazards associated with each method. After this analysis, managers can focus on logistical issues, expected production rates, and estimated costs. The cost estimates presented in this report are based on information provided (as of 2010) by U.S. Department of Agriculture, Forest Service employees, Forest Service contractors, and private industry. Figure 1—Tubular masses of resin (pitch tubes) on the bark of this tree indicate a mountain pine beetle infestation. Useful Terms and Definitions Forest Service employees traditionally use the term "hazard tree" rather than danger tree. In this report, the U.S. Department of Labor, Occupational Safety and Health Administration (OSHA) term "danger tree" is used and has the same meaning as hazard tree. Collateral Duties: Secondary work duties that are assigned in addition to an employee's primary work duties. Danger Tree (or Hazard Tree): A standing tree that presents a hazard to employees due to conditions such as, but not limited to, deterioration or physical damage to the root system, trunk, stem or limbs, and the direction and lean of the tree. —Occupational Safety and Health Standards, Title 29 of the Code of Federal Regulations (CFR) Part 1910.266(c) Any tree or its parts that will fail because of a defect and cause injury or death to people. —"Field Guide for Danger Tree Identification and Response" (2008 edition), Forest Service, Pacific Northwest Region Danger Tree Mitigation: Elimination or controlled avoidance of the dangers associated with a danger tree. Diameter at breast height (d.b.h.): The average outside bark diameter of a standing tree when it is measured at breast height (4.5 feet above the forest floor on the uphill side of the tree). Force Account Work: Work activities performed by permanent or temporary Forest Service employees rather than by outside labor. Labor Intensive Service Contract (LISC): Contracts for on-the-ground services requiring extensive hand labor including, but not limited to, tree planting, tree thinning, tree pruning, cone collection, and other forestry-related services. Qualified Person: A person who has knowledge, training, and experience in identifying danger trees, their potential failure zones, and measures to eliminate the danger. —"Field Guide for Danger Tree Identification and Response" (2008 edition), Forest Service, Pacific Northwest Region Solid Biofuel: Commercial timber fuel product derived from logging debris (also referred to as biomass). Stand Density: Number of trees (stems) per acre. Stewardship Contract: A written agreement that can help achieve land management goals while meeting local and rural community needs. This type of contract focuses on the "end result" ecosystem benefits and outcomes rather than on what is removed from the land. Additional information is available at http://www.fs.fed.us/fstoday/091106/03.0About_Us/stewardship_brochure.pdf. Tree Complexity: According to the National Wildfire Coordinating Group's Hazard Tree and Tree Felling (HTTF) Task Group, the elements of complexity include: Felling Concerns—Amount/condition of material, size, bind(s), stability, defect, overhead and surrounding hazards, and potential for tree to hang up on other trees. Environment—Slope, weather, and condition of ground for footing. Secured felling/bucking area—Area that must be established, maintained, and restricted throughout felling operations. Equipment—Equipment available, needed, and used, and its condition. Human Factors—Assessment of risk, physical condition, individual experience, confidence, attitude, judgment, and ability to communicate. Top Back \| Next \| Cover Page
T&D Home \| USDA.gov \| Site Map \| Policy and Links \| Forest Service Home \| MTDC Intranet FOIA \| Accessibility Statement \| Privacy Policy \| Non-Discrimination Statement