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Downloads: (these are explained below) Hazard Tree Inspection form (Word version). (Here is the RTF version.) Optional mapping form (Word version). (Here is the GIF version.) International Tree Failure Database reporting form (pdf file). Hazard Tree Database (zip file). |
“Improve the safety and economy of Forest Service roads, trails, facilities, and operations, and provide greater security for the public and employees.”Traditionally and currently, according to the Forest Service Manual, line officers have direct responsibility for annual inspection and management of hazard trees on campgrounds and other heavily used recreation areas. FSM 2332.11 requires removal of hazardous trees or tree limbs, with assistance from timber management, forest health management, and recreation specialists.
R2 Supplement No. 2300-94-6 (2332.1), effective 8/15/94, states:
District rangers have the responsibility for carrying out the Regional program for identifying and correcting hazardous situations at developed sites in the public sector and at undeveloped areas where concentrated public use is anticipated. Immediate corrective action will be taken on all high priority deficiencies. Sites and facilities with high priority deficiencies that cannot be corrected immediately shall remain closed or be closed until the unsatisfactory condition is corrected. Removal of hazardous trees and other corrective work shall be incorporated into the annual program of work and budgeted accordingly.As concessionaires have taken over management of most campgrounds in the Region, the situation has changed to some extent. Current permits assign responsibility for annual hazard tree inspection and removal to the concessionaire. The results of this arrangement have been variable across the Region. Some concessionaires have conducted inspections and removals or arranged for contractors to do the work. In many cases, little is done beyond removing dead trees, and in some cases even that level of effectiveness has not been reached. Proactive district personnel in some major recreational areas have become concerned at the situation in some campgrounds and have done survey work themselves or in cooperation with Forest Health Management.Inspections shall be made annually and documented on Form R2-2300-11a, Recreation Site Preseason Safety and Health Inspection, which includes tree hazard evaluation. In addition, inspection shall be made and documented at specific sites after each major disturbance, such as high wind storm. Completed inspection reports shall be filed in the individual recreation site folders on the Ranger District.
The individual conducting the inspection shall have satisfactorily completed appropriate training and demonstrated competence in recognizing and evaluating safety and health hazards, including tree hazards. The training of these individuals is the responsibility of the Forest. Assistance from the Regional Office Staffs of Forest Pest Management and Recreation Management are available if Forest personnel does not have the expertise.
Tree failures should be reported on Form R2-2300-11b, Report of Tree Failure, and forwarded to Forest Pest Management for their records. The publication "Tree Hazards: Recognition and Reduction in Recreation Sites," Technical Report R2-1 (revised 1981), provides the guidelines for evaluating hazard trees in the Region.
Because of changes in policy, permits issued from this time forward may place narrower bounds on the responsibility assigned to the permittee. Responsibility for hazard tree management may be explicitly assumed by the Forest Service again, but the future is unclear on this issue. Some Forests may go their own way on this question, such that responsibility is in the hands of the Forest Service in some cases and the concessionaire in others.
If so, plaintiffs want to know how thorough it is, how the inspectors are trained, the methodology and equipment used in the inspection, record keeping, etc. Then the questions turn to the tree that failed. When was it last inspected? What were the results? Was there any defect or indicator that might have suggested to a trained inspector that this particular tree was hazardous? A proactive inspection program can not only protect lives and property, it can ensure that managers have confidence in their ability to answer these questions.
| Table 1. Data from complete survey of selected developed recreation areas, 1997-1999. | ||||
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| North | 13 campgrounds, 281 campsites | 104 (0.37 per campsite) | 24 | 0.085 per campsite |
| South | 11 campgrounds, 324 campsites | 689 (2.1 per campsite) | 53.5 | 0.165 per campsite |
| South | 10 other recreation areas | 128 (12.8 per area) | 9.3 | 0.93 per area |
To extrapolate the data in Table 1 to the Region, we note that there are 482 developed campgrounds with a total of 9,999 campsites in the Region. Using the average of 1.24 high-hazard trees per campsite, we estimate that there are approximately 12,399 trees in the high or highest hazard category in campgrounds of the Region.
The personnel required to inspect the campgrounds in Table 1 for hazard trees can be used to estimate the size of the overall task in the Region. Based on the campground data (using the average of 0.125 person-days per campsite), a full survey of the Region would require approximately 1250 person-days. Such surveys are normally accomplished with 2- or 3-person crews. Table 2 shows the number of days it would take to survey the Region with varying numbers of personnel. Thus, 6 people (2, 3-person crews or 3, 2-person crews) working 4-5 months per year could cover the Region in approximately two years. This may be a reasonable schedule, with the alternate-year inspection being more rudimentary and limited to spring cleanup and removal of dead and obviously defective trees.
| Table 2. Days required to survey all R2 campgrounds for 1, 3 and 6 workers. | ||
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| No. of persons 1 | No. work days | No. calendar days |
| 1 | 1250 | 1825 |
| 3 | 417 | 609 |
| 6 | 208 | 304 |
This does not include the large number of developed recreation sites other than campgrounds. Inspections are required in such sites, at least near parking areas, toilets, picnic areas, etc., but in most cases the number of trees involved is much lower than in campgrounds. Also, campgrounds are often given higher priority for inspection and treatment.
In developing a hazard tree inspection program, a number of decisions need to be made. Forest Health Management is available to assist in planning and developing a program and in training field personnel in suitable inspection procedures and criteria. Here are some decisions that need to be made:
Documentation is important to provide legal evidence should an accident occur, to track the progress of the program, and to detect trends in disease and hazard development in the recreation sites. Training of inspectors should be documented. Inspection procedures and criteria (including decisions made on the issues listed) above should be described in writing. Inspection data should be saved, as well as documentation of treatment actions.
A Microsoft Access application is designed to store and summarize data from hazard tree inspections. It was developed here in R2 to accommodate the Region’s hazard tree rating system. It is used on a local computer (C drive) . Users can import data from field data recorders, spreadsheets, or enter/edit data directly. Useful summary reports and tree lists can be quickly and automatically generated to support decision-making and implementation of treatment plans. Since all USFS computers already have Microsoft Access, no software purchase is necessary. You can download it here. Unzip it to C:\Program Files and read the User's Guide.
Work the area in a logical, consistent sequence. Don't jump around. Following campsite numbering is a good idea. Record tree number, species, dbh, and mapping info as appropriate.
Assess the target for each tree. If the tree would not hit a road, major trail, structure, parking area or campsite, you can probably ignore it. If so, rate the target 2 or 1 (see form).
Look at the tree from 2-3 perspectives, close and far and all around. When you are learning, it will help to go through each defect on the form and decide if it applies. Inspectors should be able to recognize defects and understand their implications.
Based on indicators and experience, it may be necessary to check for root disease, usually using a pulaski. Examples of indicators would be thinning crown, dieback, reduced height growth, basal resinosis, exposed decay in butt or roots.
Also based on indicators, you may need to increment core or drill the tree to assess internal stem decay. Such indicators include wounds and bird cavities. Trees are rated in the highest hazard cavity if the remaining, undecayed, sound shell is less than 1/3 of the radius (use dbh/2 to get radius, not the core).
Calculate the rating. In some cases, you may feel the rating does not accurately reflect the hazard of the tree. Tree inspection and hazard rating are a combination of science and art: do what experience and sound judgment tell you is right, but make notes in the space provided about what you do. If necessary use a supplemental notebook. Even if the rating seems reasonable, use the notes column to record details on the defects, such as identity of the root pathogen, canker, conk, etc.
Here, in summary, are things to look for in a typical inspection:
Callus forms at the margin of injured cambium and grows outward to cover the wound. If all is well, the callus margins will meet and seal over the wound. Sometimes, the callus tends to curl inward, or inroll, during growth. This is sometimes called “ram's-horning.” If this happens, the callus never meets and seals properly. Instead, the bark covered surfaces of the callus rolls meet. As growth rings are added, the callus sides push against one another, leading to formation of cracks. Also, tension generated in the stem can lead to formation of secondary cracks elsewhere. Inrolled callus might might be expected where the wound surface is concave. The callus margin follows the concavity as it grows, increasing the likelihood that the callus surfaces will meet before the margins.
Here are some steps to avoid such damage:
Maintain bumpers to protect trees from vehicles.
The only exception is with elms and oaks. In areas where the two wilt diseases, Dutch elm disease and Oak wilt, are of concern, fresh wounds should be covered with some kind of dressing to prevent access of the vectors to the wound area.
If we are to maintain developed recreation sites indefinitely, it is important to develop a vegetation management plan for each site. Such a document should take into account current conditions of the vegetation (including canopy, regeneration, shrubs, etc.), management objectives such as aesthetics and screening, potential pathways of stand development in the future, current and potential development of insects and diseases that may affect those pathways, and alternative approaches to meeting the objectives in the future. We know that the trees that make our campgrounds so beautiful will, at some point in the future, either die, fall, or be removed because we can no longer tolerate the risk that they present. There is no better time than now to plan for replacement of those trees.
The Rocky Mountain Region produced a guidebook to help managers of recreation and administrative sites develop and implement vegetation management plans. A new appendix considers detailed issues involved in revegetation of campgrounds following mortality due to bark beetles:
Printed copies of the guide are also available from Renewable Resources in the Regional Office and from Forest Health Management Service Centers.
As indicated in the FSM R2 Supplement cited above, the Region formerly had a tree failure reporting system. This system has provided information on failed hazard trees that was useful in improving criteria for detecting hazard trees and also provided an indication of particular problems in the Region that needed to be addressed.
An international tree failure reporting system has now been established, the International Tree Failure Database. It was initiated by USDA Forest Service in cooperation with the International Society of Arboriculture. The new system uses a paper form for gathering failure data in the field. Reports are then entered into an online database. A PDA-based data entry system is also available. Training is required to get a username and password so that reports can be entered online. The regular hazard tree training provided by R2 Forest Health Management incorporates the needed information. Federal and state managers in the area served by R2 Forest Health Management who have not had the training can contact their Forest Health Management service center for information about submitting reports.
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