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United States Department of Agriculture

FVS Models & Event Monitor Files

Mountain Pine Beetle Risk Rating Event Monitor Addfiles

The MPB in LPP Risk Rating EM Addfiles (I & II)

There are two different Event Monitor (EM) applications that calculate a mountain pine beetle (MPB) risk (or hazard) rating for stands of lodgepole pine (LPP):

  • I. The first (mpb_lpp_amman.kcp) calculates risk based on the system of Amman et al. 1977.
  • II. The second (mpb_lpp_RT.kcp) calculates risk based on the system of Randall and Tensemeyer, 2000.

mountain pine beetle damage

Transition area where lodgepole pine and ponderosa pine intersect and are both attacked by mountain pine beetle. Photo by Whitney Cranshaw, Colorado State University.

The MPB in LPP Risk Rating EM Addfile (I) Based on Amman et al. 1977

What is it?

The MPB in LPP Risk Rating EM Addfile (I) (mpb_lpp_amman.kcp) is an FVS keyword component file that calculates a stand's hazard rating based on a system proposed by Amman et al. 1977. This Event Monitor application does not perform any stand management activities; it schedules only FVS COMPUTE statements.

The risk rating system was designed for mountain pine beetle (MPB; Dendroctonus ponderosae Hopkins) in lodgepole pine (LPP; Pinus contorta var. latifolia Engelmann) in the Rocky Mountains. The EM Addfile provides a numerical "risk susceptibility score" that ranks the risk of stands to attack by the MPB.

How this Application Determines Risk

The overall risk rating score is determined from three risk factors:

  • elevation/latitude
  • average age
  • average DBH (of trees greater than 5 inches DBH)

Stands are assigned a risk factor score of 1, 2, or 3, (for each risk factor) depending upon the stand conditions for each risk factor. The three risk factor scores are then multiplied together to arrive at a "risk susceptibility" score (ranging from 1-27).

The application reports a final numerical rating. It is up to the user to interpret the numerical rating. Amman et al (1977) interpret the scores as follows:

If the product of the three scores (risk factor 1 • risk factor 2 • risk factor 3) equals:

  • 1-9 = the overall risk is considered LOW
  • 12-18 = the overall risk is considered MODERATE
  • 27 = the overall risk is considered HIGH

The product of a stands risk factor values determines the overall risk rating for a stand shown in Table 1 for MPB (I) .

Table 1 for MPB (I) Risk factors, and associate risk factor values, of the Amman et al (1977) risk rating system
RISK FACTOR 1 RISK VALUE RISK FACTOR 2 RISK VALUE RISK FACTOR 3 RISK VALUE
Elevation/Latitude Age (yrs) Average DBH+ (in.)
High Elevation 1 < 60 1 < 7 1
Moderate Elevation 2 60 - 80 2 7 - 8 2
Low Elevation 3 > 80 3 > 8 3

+The average DBH is for trees greater than 5 inches DBH.

The elevational/latitudinal ranking is determined from a hypothesized linear relationship between elevation, latitude, and risk. The program requires that the user enter appropriate "elevation thresholds" into the EM addfile (separating "high" elevation from "moderate" elevation, and "moderate" elevation from "low"). Details regarding how users should configure the EM addfile to appropriately rate their stands on this elevational/latitudinal factor can be found in the User's Guide accompanying this EM addfile.

Download the Mountain Pine Beetle I Risk Rating EM Addfile and User's Guide

  1. The FVS Mountain Pine Beetle (I) Package link will download a self-extracting Zip file. You may download this .exe file anywhere on your computer.
  2. Once downloaded, double-click the .exe file to begin the extraction process.
  3. Although you may extract the files to anywhere on your computer, we recommend that you use the default extraction locations.
  4. The files will be extracted into c:/fvs_data. (If you do not have this directory, the extraction process will create it.) The files will include the Mountain Pine Beetle EM (I) Addfile (mpb_lpp_amman.kcp and the accompanying User's Guide.

The MPB in LPP Risk Rating EM Addfile (II) Based on Randall and Tensmeyer 2000

What is it?

The MPB in LPP Risk Rating EM Addfile (II) (mpb_lpp_RT.kcp) is an FVS keyword component file that calculates a stand's hazard rating based on a system developed by Randall and Tensmeyer (2000). This application does not perform any stand management activities; it schedules only FVS COMPUTE statements.

The risk rating system was designed for mountain pine beetle (MPB; Dendroctonus ponderosae Hopkins) in lodgepole pine (LPP; Pinus contorta var. latifolia Engelmann) in the Rocky Mountains. It represents a "hybridization" of the systems proposed by Amman et al. (1977) and Shore and Safranyik (1992). The application provides a numerical "risk susceptibility score" that ranks the risk of stands to attack by the MPB.

How this Application Determines Risk

This EM addfile performs a set of sequential steps to determine a numerical risk rating score for all cycle-beginning years of an FVS simulation. Factors considered in the hazard rating logic include:

  • % of total basal area that is lodgepole pine
  • total stand basal area
  • total trees per acre
  • stand elevation
  • stand age
  • average DBH of lodgepole pine (of trees greater than 5 inches)
The step-wise progression of logic is presented in table 1, below. The application reports only the numerical rating; it is up to the user to qualitatively interpret the numeric score. (The qualitative interpretation of the numerical rating-as published in Randall and Tensmeyer 2000-is given in the table's final column.)

Table 1 abbreviations used: BA = basal area; TPA = trees per acre; QMD = quadratic mean diameter.

Table 1 for MPB (II) Step-wise logic of the Randall and Tensmeyer risk rating system, as followed by the mpb_lpp_RT.kcp EM Addfile
Step MPB in LPP Hazard Rating Logic
(Performed stepwise)
Numerical Rating Hazard Rating
1 If % BA LPP = 0 1 Extra Low
2 If % of BA in LPP < 25% 2 Low
3 If stand BA <80 or >250 sq ft / acre 3 Low
4 If TPA > 3" is <100 or > 800 4 Low
5 If QMD of LPP > 5" DBH is < 6" dbh 5 Low
6 If elevation (in m) > Threshold A 6 Low
7 If stand age < 60 yrs 7 Low
8 If % of BA in LPP is 25-50% 8 Moderate
9 If stand BA is 80-120 sq ft / acre 9 Moderate
10 If TPA >3" is 100-300 or 600-800 10 Moderate
11 If QMD of LPP >5" DBH is < 8" dbh 11 Moderate
12 If elevation (in m) > Threshold B 12 Moderate
13 If stand age >= to 60 yrs and < 80 yrs 13 Moderate
14 Else 14 High

Download the Mountain Pine Beetle II Risk Rating EM Addfile and User's Guide

  1. The FVS Mountain Pine Beetle (II) Package link will download a self-extracting Zip file. You may download this .exe file anywhere on your computer.
  2. Once downloaded, double-click the .exe file to begin the extraction process.
  3. Although you may extract the files to anywhere on your computer, we recommend that you use the default extraction locations.
  4. A number of files will be extracted into c:/fvs_data. (If you do not have this directory, the extraction process will create it.) The files will include the Mountain Pine Beetle EM (II) Addfile (mpb_lpp_RT.kcp and the accompanying User's Guide.

Event Monitor Output

Output from both of these EM addfiles will include the values of all variables used in calculating the hazard rating score(s) as well as the hazard rating scores themselves. Output is written to the standard FVS output table. Output may also be written to (1) a stand-alone text file via the Compute post-processor available in Suppose, or (2) to an output database via FVS’s Database Extension, or both.

References

Amman, Gene D, Mark D McGregor, Donn B Cahill, and William H Klein. 1977. Guidelines for reducing losses of lodgepole pine to the mountain pine beetle in the Rocky Mountains. USDA Forest Service Gen. Tech. Rep. INT-36. Intermountain Forest and Range Exp. Sta., Ogden, UT. 22pp.

Crookston, Nicholas L. 1990. User's guide to the Event Monitor: Part of Prognosis Model Version 6. USDA Forest Service Gen. Tech. Rep. INT-275. Intermountain Res. Sta., Ogden, UT 29pp.

Randall, Carol B, and Greg Tensmeyer. 200. Hazard rating system for mountain pine beetle in lodgepole pine using the Oracle database and the Forest Service IBM platform. Forest Health Protection Report 00-6. USDA Forest Service, Northern Region, Missoula, MT. 5pp.

Shore, T, and L Safranyik. 1992. Susceptibility and risk rating systlem for the mountain pine beetle in lodgepole pine stands. Forestry Canada BC-X-336.