United States
Department of
Agriculture
File Code:
Route To:
Subject:
Prepared
by:
Forest
Service
Plumas
National
Forest
159 Lawrence Street
P.O. Box 11500
Quincy, CA 95971-6025
95971
(530) 534-7984
7984 Text (TDD)
(530) 283-2050
2050 Voice
Date:
January 20,, 2010
20
FY 2009 Progress Report on HFQLG Pilot Project Monitoring
Effects of the Pilot Project Fuel Treatments on Wildfires and Air Quality
Pete Duncan, Plumas NF; Kyle Merriam, Province Ecologist;; Colin Dillingham,
HFQLG Monitoring Coordinator; Brandon Collins, PSW Fire Ecologist.
The HFQLG Monitoring Plan addresses the 8 following smoke management and wildfire
trend questions. These questions are answered below based on monitoring data collected through
the Treated Stand Structure Monitoring program and information provided by district offices
within the HFQLG Pilot Project Area:
ilviculture and fuel treatments meet … fuels and other stand objectives?
Question 1: Do silviculture
Question 9: Were provisions of the Smoke Management Plan implemented?
Question 26: Do prescribed fire activities meet air quality standards?
Question 27: Do prescribed fires create a nuisance in terms of air quality?
Question 23: What is the trend in large fi
fire frequency?
Question 24:: What is the trend in severity of large fires on acres burned?
Question 25: What is the effect of treatments on fire behavior and suppression?
Question 1) Do silviculture and fuel treatments meet … fuels and other stand objectives?
HFQLG activities in Defensible Fuel Profile Zones (DFPZs) are intended to reduce fire
intensities to a level where fire suppression activities can be effective. One criterion for
evaluating fuel treatment effectiveness is whether predicted sur
surface
face flame lengths are reduced to
less than 4 feet at 90-percentile
percentile weather conditions. Field data were collected in 79 DFPZs both
pre- and post-treatment.. These data were used tto model predicted fire behavior,, including surface
flame lengths, using the Fire
ire and Fuels Extension to the Forest Vegetation Simulator
(FFE)(Reinhardt and Crookston 2003). FFE predicted mean pre-treatment
treatment flame lengths
length to be
4.5 ft prior to treatment. Mean predicted flame lengths were reduced 3.2 ft one year after DFPZ
construction (Figure 1).. This 1.3 ft reduction in predicted flame length was statistically
significant based on paired-tt tests (t-test value =540.05, p < 0.01) conducted with SAS version
9.2 (SAS
S Institute Inc., Cary, NC, USA)
USA). Most
ost DFPZ plots have not had understory
underst
burn
treatments completed to date, so data are not yet available to complete a separate analysis of
underburn treatments.
Caring for the Land and Serving People
Printed on Recycled Paper
Figure 1. Predicted surface flame lengths pre- and post- DFPZ implementation.
Predicted Flame Length (ft)
5
4
3
2
1
0
Pre-Treatment
Post-Treatment
.
HFQLG activities in DFPZs also have silviculture objectives. One of these objectives is
to reduce mortality of trees during wildfire events. Field data were collected in 79 DFPZs both
pre- and post-treatment and run through FFE using 90th-percentile weather conditions to
determine if predicted mortality rates were affected by treatment implementation.
Mean predicted tree mortality rates declined significantly after DFPZ implementation,
from 91% of all trees present prior to treatment to a predicted mean mortality rate of 77% posttreatment (t-test value =4.3, p < 0.01).
Figure 1. Predicted mortality rates pre- and post- DFPZ implementation.
Predicted Mortality (%)
1
0.8
0.6
0.4
0.2
0
Pre-treatment
Post-treatment
Question 9) Were provisions of the Smoke Management Plan implemented?
Smoke Management Plans (SMP) are prepared in coordination California Air Resources
Board, multiple counties (Lassen, Butte, Shasta, Butte, Tehama, and Plumas) and the Northeast
Air Alliance. In part, the purpose of the SMP is to describe methods used to mitigate smoke
related impacts to local and regional air quality.
The objective of this question is to determine if burns meet the provisions of Smoke
Management Plans (SMP) as defined in the California Air Resources Board Title 17 and the
EPA’s Interim Air Quality Policy. The monitoring protocol is to conduct post-burn evaluations
to assess adherence to SMP provisions for all burns.
In FY09 there were no reported violations of provisions of Smoke Management Plans for
prescribed burn activities implemented within the HFQLG Pilot Project Area. No Class I
Airsheds were impacted and the Forest Service and local Air Quality Districts received no formal
smoke complaints.
In summary, provisions of the Smoke Management Plan were implemented for
prescribed burn activities within the HFQLG Pilot Project Area.
Question 26) Do prescribed fire activities meet air quality standards?
The objective of this question is to determine if prescribed fire activities are in
compliance with air quality standards. The monitoring protocol is to assess adherence to Smoke
Management Plan provisions for burns utilizing data from Air Quality Management District
(AQMD) recorders and/or portable recorders to assess impacts to air quality at receptor sites.
In FY09, there were no reported violations of air quality standards due to prescribed burn
activities within the HFQLG Pilot Project Area.
Question 27) Do prescribed fires create a nuisance in terms of air quality?
The objective of this question is to determine if prescribed fire activities resulted in
official smoke complaints and/or resulted in prescribed burns being discontinued due to these
complaints. The monitoring protocol is to log the number of complaints (date, time, telephone
number, address and type of impact) and to track the number of projects discontinued due to
complaints about air quality resulting from prescribed burns.
Approximately 10,309 acres of prescribed burning were implemented across the HFQLG
Pilot Project Area in FY09 with no official complaints (Table 1). The absence of violations or
complaints can be explained by extensive coordination and communication of prescribed burn
activities between ranger districts, air districts and the public. This included public contact,
which consisted of phone calls, press releases, door-to-door visits, and public information booths
set up near burn project sites to directly answer questions and address concerns from the public.
Land managers that conduct burning within the Northeast Air Alliance area (which the
Pilot Project is part of) coordinate burn activities via e-mail daily, notifying each of the of the
burn location, number of acres and duration. A smoke conference call also takes place on a daily
basis and involves the California Air Resources Board, local air district managers, meteorologists
from the Predictive Services Centers in northern and southern California, and prescribed burners.
The smoke call is used to exchange weather and prescribed burn information between all the
participating parties.
Table 1. Total acres of under burning and pile burning and resulting smoke complaints for 20022009
Forest
Number of
Year
Acres Burned
Reporting
Complaints
2002
Plumas
5,045
3
2003
Plumas
4,280
0
2004
All HFQLG
10,778
0
2005
All HFQLG
14,310
16
2006
All HFQLG
5,863
7
2007
All HFQLG
9,792
0
2008
All HFQLG
7,553
0
2009
All HFQLG
10,309
0
Question 23: What is the trend in large fire frequency?
The objective of this question is to determine if fire frequency, indicated by fire size and
number, are exhibiting an upward or downward trend, and if this trend has been influenced by
implementation of the HFQLG pilot project.
To evaluate fire trends within the HFQLG project area we used the 2007 fire atlas developed
by the California Department of Forestry and Fire Protection (2008). This GIS data layer
contains all fires over 10 acres and greater recorded on federal lands in California since 1900.
This is the most comprehensive, long-term database of fire polygons in the western United
States. A considerable amount of time has been spent validating and updating the data base over
the last decade by USFS and Department of Interior staff and is it currently in a more complete
state than previous versions. Although it is subject to errors (see Morgan et al. 2001), this dataset
represents the best available information we have at this time.
Fire size and mean fire size data were log transformed to improve normality. Trends in fire
size, number of fires, and mean fire size were evaluated with Autoregressive Integrated Moving
Average (ARIMA) time domain regression using Box-Jenkins techniques for model
identification and estimation.
ARIMA analysis found a significant increasing linear trend in mean fire size since 1900. The
number of acres burned also indicated a linear increase, although this trend was not significant at
the 0.05 level (p=0.09). On the other hand, number of fires since 1900 has not increased (Figure
1). These data agree with other larger scale analyses that have been conducted for the entire
Sierra Nevada and southern Cascade ranges (Miller et al. 2008, Miller and Safford 2008)
showing that fire size has shown a linear increase over the past century. However, because the
HFQLG pilot project has not been implemented in its entirety (Pinchot 2008), it is difficult to
determine the potential effect of HFQLG on large fire frequency at this time.
Figure 1. ARIMA results for mean fire size, fire number and acres burned in the HFQLG project
area
since 1900. Values for mean fire size and acres burned are shown on a logarithmic scale.
Question 24: What is the trend in severity of large fires on acres burned? The objective of
this question is to determine if fire severity is exhibiting an upward or downward trend, and if
this trend has been influenced by implementation of the HFQLG pilot project.
To answer this question we used fire severity mapping produced by the USDA Forest Service
(Miller and Thode 2007) for all fires greater than 100 acres from 1984 to 1999 for certain areas
in the Sierra Nevada. Thirty-nine fires have been mapped for the HFQLG project area through
this program. For each fire we calculated the area that was mapped as high severity (greater than
75% basal area mortality) and converted this to a percentage of total fire size. This percentage
data was arcsine square root transformed to improve normality. Trends in percent high severity
fire since 1984 were then evaluated with Autoregressive Integrated Moving Average (ARIMA)
time domain regression using Box-Jenkins techniques for model identification and estimation.
ARIMA found a significant linear increase in the percent of area burning at high severity
across the HFQLG project area since 1984 (Figure 2). A pattern of increasing fire severity has
also been documented for the entire Sierra Nevada and the southern Cascade mountains (Miller
et al. 2008, Miller and Safford 2008). However, because the HFQLG pilot project has not been
implemented in its entirety (Pinchot 2008), it is difficult to determine the potential effect of
HFQLG on fire severity at this time.
Figure 2. ARIMA model results for percent of high severity fires since 1984.
Question 25: What is the effect of treatments on fire behavior and suppression? Within the
Pilot Project area the Dow fire (Eagle Lake RD, Lassen NF, 1999), Cone fire (Blacks
Experimental Forest, Lassen NF, 2002), the Stream fire (Mt Hough RD, Plumas NF, 2001), the
Boulder Complex (Mt. Hough RD, Plumas NF, 2006), Wheeler and Moonlight fires, (Mt Hough
RD, Plumas NF, 2007) and Calpine fire (Sierraville RD, Tahoe NF, 2007) have all been
referenced in prior years to address this question and the reports are part of the Pilot Project
Record. In 2008, 2 wildfires (Peterson and Rich) impacted fuel treatment areas. DFPZ
effectiveness studies have been completed for both these fires and this information is
summarized and available on the HFQLG website http://www.fs.fed.us/r5/hfqlg.
Preliminary findings on the effects of treatments on fire behavior and suppression on these fires
are that the Defensible Fuel Profile Zone (DFPZ) fuel breaks slowed the fire enabling
suppression resources to concentrate their efforts on higher priority areas closer to communities
and defer suppression efforts within the fuel break. In addition, the intensity of the fire was lower
in the treated areas and preliminary reconnaissance indicates greater tree survival in the treated
versus untreated area.
In addition to the examples from actual fires, modeling has been conducted for an 18,000 ha
study area located in Meadow Valley (Plumas NF), which is within the Pilot Project area. The
modeling efforts involve simulating fire spread and fire behavior for a single theoretical
‘problem fire’ (Bahro et al. 2007), as well as simulating fire occurrence throughout the study
area based on 1000 randomly located ignitions. Both of these approaches have been applied to
two separate Meadow Valley landscapes; one captures vegetation and fuel conditions prior to
implementation of HFQLG silvicultural and fuel treatment activities, and the other represents the
fuel and vegetation conditions following HFQLG treatment implementation. Results demonstrate
substantial reduction in both ‘problem fire’ size and in area burned at higher flame lengths
(Table 2, Figure 1). Across the Meadow Valley study area burning probability was reduced as a
result of HFQLG treatments, particularly towards the north-east, or down-wind, portion of the
study area (Figure 2). This information is presented in a manuscript that is currently under peerreview (Moghaddas et al. in review).
Further analysis of the HFQLG treatments in Meadow Valley is underway. In this analysis the
Meadow Valley landscape is modeled several decades into the future to attempt to assess
HFQLG treatment longevity. Additionally, this analysis will estimate potential vulnerability of
forest stands to wildfire across the Meadow Valley study area prior to and following HFQLG
treatment implementation. This vulnerability assessment will be used to identify areas of
substantial habitat alteration if a fire were to occur within the study area. This analysis will be
presented in a manuscript that is currently in preparation.
Table 2. Characteristics of a modeled ”problem fire” for the pre- and post-treatment Meadow
Valley landscape. Area burned is summarized using two flame length break values. These flame
length values are based on operational constraints for fire suppression activities.
Fire size
(ac)
Average
flame
length
(ft)
Pre
22,674
3.1
Post
13,761
2.7
Treatment
phase
Area burned > 8 ft flame
Area burned > 11 ft flame
length (ac)
length (ac)
(proportion of burned area) (proportion of burned area)
9321
(0.41)
5127
(0.37)
7149
(0.31)
3820
(0.28)
Figure 1.Predicted wildfire size and average flame length, Meadow Valley area, before and after
HFQLG treatments
Before Treatment
After Treatment
Figure 2
Literature Cited
Bahro B, Barber KH, Sherlock JW and Yasuda DA 2007. Stewardship and fireshed assessment:
a process for designing a landscape fuel treatment strategy. In Restoring fire-adapted
ecosystems: 2005 National Silviculture Workshop, pp. 41-54. U. S. Department of
Agriculture, Forest Service, Pacific Southwest Research Station, Tahoe City, California.
California Department of Forestry and Fire Protection. 2007. Fire perimeters. Sacramento,
California, USA: http://frap.cdf.ca.gov/data/frapgisdata/select.asp. Accessed: January 1,
2009.
Miller, Jay D. and Andrea E. Thode. 2007. Quantifying burn severity in a heterogeneous
landscape with a relative version of the delta Normalized Burn Ratio (dNBR). Remote
Sensing of Environment 109(1): 66-80.
Miller, Jay D. H. D. Safford, M. Crimmins. and A. E. Thode. 2009. Quantitative Evidence for
Increasing Forest Fire Severity in the Sierra Nevada and Southern Cascade Mountains,
California and Nevada,USA. Ecosystems 12: 16-32.
Miller, Jay D. and H. D. Safford. 2008 Sierra Nevada. Fire Severity Monitoring. 1984-2004.
United States. Department of .Agriculture. Forest Service. Pacific Southwest. Region. R5TP-027-027. August 2008. 102 pp.
Moghaddas JJ, Collins BM, Menning K, Moghaddas EY, and Stephens SL. in review. Fuel
treatment effects on modeled landscape level fire behavior in the northern Sierra Nevada.
Canadian Journal of Forest Research.
Morgan P, Hardy C, Swetnam TW, Rollins MG, Long DG. 2001. Mapping fire regimes across
time and space: understanding coarse and fine-scale patterns. Int J Wildland Fire 10: 1–14.
Pinchot Institute. 2008. Report of the Herger-Feinstein Quincy Library Group Independent
Science Panel to the USDA Forest Service (Phase One). 104 pp.
Reinhardt, E.D.; Crookston, N.L. Technical Editors. 2003. The Fire and Fuels Extension to the
Forest Vegetation Simulator. Rocky Mountain Research Station RMRS-GTR-116. 218 p