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At least 793 records · Page 44Linked to original sources
USGS2010

Floral and nesting resources, habitat structure, and fire influence bee distribution across an open-forest gradient

Given bees' central effect on vegetation communities, it is important to understand how and why bee distributions vary across ecological gradients. We examined how plant community composition, plant diversity, nesting suitability, canopy cover, land use, and fire history affected bee distribution across an open-forest gradient in northwest Indiana, USA, a gradient similar to the historic Midwest United States landscape mosaic. When considered with the other predictors, plant community composition was not a significant predictor of bee community composition. Bee abundance was negatively related to canopy cover and positively to recent fire frequency, bee richness was positively related to plant richness and abundance of potential nesting resources, and bee community composition was significantly related to plant richness, soil characteristics potentially related to nesting suitability, and canopy cover. Thus, bee abundance was predicted by a different set of environmental characteristics than was bee species richness, and bee community composition was predicted, in large part, by a combination of the significant predictors of bee abundance and richness. Differences in bee community composition along the woody vegetation gradient were correlated with relative abundance of oligolectic, or diet specialist, bees. Because oligoleges were rarer than diet generalists and were associated with open habitats, their populations may be especially affected by degradation of open habitats. More habitat-specialist bees were documented for open and forest/scrub habitats than for savanna/woodland habitats, consistent with bees responding to habitats of intermediate woody vegetation density, such as savannas, as ecotones rather than as distinct habitat types. Similarity of bee community composition, similarity of bee abundance, and similarity of bee richness between sites were not significantly related to proximity of sites to each other. Nestedness analysis indicated that species composition in species-poor sites was not merely a subset of species composition at richer sites. The lack of significant proximity or nestedness effects suggests that factors at a small spatial scale strongly influence bees' use of sites. The findings indicate that patterns of plant diversity, nesting resource availability, recent fire, and habitat shading, present at the scale of a few hundred meters, are key determinants of bee community patterns in the mosaic open-savanna-forest landscape. ?? 2010 by the Ecological Society of America.

Ecological Applications↗
USGS2014

Beyond reducing fire hazard: fuel treatment impacts on overstory tree survival

Fuel treatment implementation in dry forest types throughout the western United States is likely to increase in pace and scale in response to increasing incidence of large wildfires. While it is clear that properly implemented fuel treatments are effective at reducing hazardous fire potential, there are ancillary ecological effects that can impact forest resilience either positively or negatively depending on the specific elements examined, as well as treatment type, timing, and intensity. In this study, we use overstory tree growth responses, measured seven years after the most common fuel treatments, to estimate forest health. Across the five species analyzed, observed mortality and future vulnerability were consistently low in the mechanical-only treatment. Fire-only was similar to the control for all species except Douglas-fir, while mechanical-plus-fire had high observed mortality and future vulnerability for white fir and sugar pine. Given that overstory trees largely dictate the function of forests and services they provide (e.g., wildlife habitat, carbon sequestration, soil stability) these results have implications for understanding longer-term impacts of common fuel treatments on forest resilience.

Ecological Applications↗
USGS2010

A new process for organizing assessments of social, economic, and environmental outcomes: Case study of wildland fire management in the USA

Ecological risk assessments typically are organized using the processes of planning (a discussion among managers, stakeholders, and analysts to clarify ecosystem management goals and assessment scope) and problem formulation (evaluation of existing information to generate hypotheses about adverse ecological effects, select assessment endpoints, and develop an analysis plan). These processes require modification to be applicable for integrated assessments that evaluate ecosystem management alternatives in terms of their ecological, economic, and social consequences. We present 8 questions that define the steps of a new process we term integrated problem formulation (IPF), and we illustrate the use of IPF through a retrospective case study comparing 2 recent phases of development of the Fire Program Analysis (FPA) system, a planning and budgeting system for the management of wildland fire throughout publicly managed lands in the United States. IPF extends traditional planning and problem formulation by including the explicit comparison of management alternatives, the valuation of ecological, economic and social endpoints, and the combination or integration of those endpoints. The phase 1, limited-prototype FPA system used a set of assessment endpoints of common form (i.e., probabilities of given flame heights over acres of selected land-resource types), which were specified and assigned relative weights at the local level in relation to a uniform national standard. This approach was chosen to permit system-wide optimization of fire management budget allocations according to a cost-effectiveness criterion. Before full development, however, the agencies abandoned this approach in favor of a phase 2 system that examined locally specified (rather than system-optimized) allocation alternatives and was more permissive as to endpoint form. We demonstrate how the IPF process illuminates the nature, rationale, and consequences of these differences, and argue that its early use for the FPA system may have enabled a smoother development path.

Integrated Environmental Assessment and Management↗
USGS2021

Time since burning and rainfall characteristics impact post-fire debris flow initiation and magnitude

The extreme heat from wildfire alters soil properties and incinerates vegetation, leading to changes in infiltration capacity, ground cover, soil erodibility, and rainfall interception. These changes promote elevated rates of runoff and sediment transport that increase the likelihood of runoff-generated debris flows. Debris flows are most common in the year immediately following wildfire, but temporal changes in the likelihood and magnitude of debris flows following wildfire are not well constrained. In this study, we combine measurements of soil-hydraulic properties with vegetation survey data and numerical modeling to understand how debris-flow threats are likely to change in steep, burned watersheds during the first 3 years of recovery. We focus on documenting recovery following the 2016 Fish Fire in the San Gabriel Mountains, California, and demonstrate how a numerical model can be used to predict temporal changes in debris-flow properties and initiation thresholds. Numerical modeling suggests that the 15-minute intensity-duration (ID) threshold for debris flows in post-fire year 1 can vary from 15 to 30 mm/hr, depending on how rainfall is temporally distributed within a storm. Simulations further demonstrate that expected debris-flow volumes would be reduced by more than a factor of three following 1 year of recovery and that the 15-minute rainfall ID threshold would increase from 15 to 30 mm/hr to greater than 60 mm/hr by post-fire year 3. These results provide constraints on debris-flow thresholds within the San Gabriel Mountains and highlight the importance of considering local rainfall characteristics when using numerical models to assess debris-flow and flood potential.

Environmental Engineering and Geology↗
USGS1984

Post-fire recovery of California coastal sage scrub

Postfire regeneration of the shrub and herb vegetation on eight coastal slopes of California coastal sage scrub was studied in the first two growing seasons after fire. All shrub species resprouted with the exception of the suffrutescent Lotus scoparius , though it is not known if this species was alive prior to the fire. It was estimated that 70% of the prefire shrub populations resprouted and these sprouts covered one third of the ground surface by the end of the second season. In contrast to chaparral, seedling establishment from soil-stored seed was low (∼ 102-103/ha) in the 1st postfire year. Resprouts of most major species ( Artemisia californica , Encelia californica , Haplopappus squarrosus , Eriogonum cinereum ) flowered and set seed in the 1st year. Seedling densities were ∼ 104-106/ha in the 2nd year. Herbs dominated the first postfire season vegetation in number of species, cover and biomass. The magnitude of the postfire herb flora was comparable to that in chaparral after fire and included many of the same species. On several slopes, "pyrophyte endemic" annuals ( Lupinus succulentus , Lotus salsuginosus , Phacelia parryi ) dominated the first season and were rare or absent in the 2nd year. One major distinction between these coastal sage sites and chaparral was that resprouting perennial herbs dominated some slopes in the first postfire season and most slopes in the second season in coastal sage. Seedling recruitment of perennial herbs was rare; 26 of the 28 species were present only as resprouts. Total herb cover was markedly lower in the 2nd year despite the fact that it was a wetter year. Between the 1st and 2nd years, shrub cover ∼ doubled, largely from resprouts, annual herb cover declined markedly and perennial herb cover remained relatively constant. The perennial bunchgrass Stipa lepida was an important component of the herb flora on all slopes and was the only species (herb or shrub) to exceed 1/m2 on all eight slopes.

California↗
USGS2001

Florida panther habitat use response to prescribed fire

The Florida panther ( Puma concolor coryi ) is one of the most endangered mammals in the world, with only 30-50 adults surviving in and around Florida Panther National Wildlife Refuge and the adjacent Big Cypress National Preserve. Managers at these areas conduct annual prescribed burns in pine ( Pinus sp.) as a cost-effective method of managing wildlife habitat. Our objectives were to determine if temporal and spatial relationships existed between prescribed fire an panther use of pine. to accomplish this, we paired fire-event data from the Refuge an the Preserve with panther radiolocations collected between 1989 and 1998, determined the time that had elapsed since burning had occurred in management units associated with the radiolocations, and generated a frequency distribution based on those times. We then generated ant expected frequency distribution, based on random use relative to time since burning. This analysis revealed that panther use of burned pine habitats was greatest during the first year after a management unit was burned. Also, compositional analysis indicated that panthers were more likely to position their home ranges in areas that contained pine. We conclude that prescribed burning is important to panther ecology. We suggest that panthers were attracted to <1-year-old burns because of white-tailed deer ( Odocoileus virginianus ) and other prey responses to vegetation and structural changed caused by the prescribed fires. The strong selection for stands burned within 1 year is a persuasive indication that it is the burning in pine, rather than the pine per se, that most influenced habitat use. Before burning rotation lengths are reduced, however, we suggest managers determine effects of shorter burning intervals on vegetation composition and evaluate the landscape-scale changes that would result.

Florida↗
USGS2006

Fire severity and plant age in postfire resprouting of woody plants in sage scrub and chaparral

Postfire resprouting by woody plants confers a marked advantage in rate of recovery over species that regenerate entirely from seed. However, the predictability of this advantage varies markedly between species, with some showing nearly 100% rootcrown survival and others often much lower. This study examined patterns of fire-caused mortality and tested the relative importance of fire severity and plant age between various shrubs and subshrubs characteristic of chaparral and sage scrub associations. Resprouting success varied from about 10% for Eriogonum fasciculatum to a high of 98% for Quercus berberidifolia . For most of the shrub species, skeletons of resprouting plants were significantly taller than those of dead individuals of the same species, indicating less biomass consumption, and thus lower severity fires were associated with higher resprouting success. This pattern was less strongly the case with sage scrub species. Shrubs and subshrubs, however, differed in the effect of aboveground plant age (as estimated by basal diameter) on resprouting success. For most chaparral shrubs, age was not related to resprouting success, whereas in four out of five subshrub species, including Artemisia californica , Eriogonum fasciculatum , Salvia leucophylla , and S. mellifera , the youngest plants exhibited the highest resprouting success. I hypothesize that the reason for this inverse relationship between age and resprouting in certain sage scrub species is that, as these subshrubs age, there is a tendency to loose the resprouting ability and the mechanism is quite possibly because adventitious buds responsible for sprouting become buried by woody tissues. Patterns of character evolution in these sage scrub lineages support the hypothesis that the herbaceous perennial mode of seasonal aestivation evolved early and lignification is a more recently derived trait and this may have negative effects on resprouting as the plant ages.

Madroño↗
USGS2015

Synthesis of current knowledge on post-fire seeding for soil stabilization and invasive species control

The General Accounting Office has identified a need for better information on the effectiveness of post-fire emergency stabilization and rehabilitation methods used by the U.S. Forest Service and Department of Interior (DOI) agencies. Since reviews were published on treatment effectiveness in the early 2000s, treatment choices have changed and increased monitoring has been done. Greater use of native species has added substantially to burned area emergency response (BAER) treatment costs, for example, but quantitative data on this treatment were scarce in earlier reviews. We synthesized current information on the effectiveness of post-fire seeding for both soil stabilization and for prevention of the spread of invasive species in rangelands. We reviewed published literature (peer-reviewed and “gray”) and agency monitoring reports, as well as compiled and analyzed quantitative data in agency files. Products of this review include a web-accessible database of monitoring reports and published information, a scientific journal paper summarizing findings of scientific studies, an annotated bibliography of peer-reviewed papers, a summary report published as a General Technical Report that will be available online (in progress), and presentations to scientific meetings and BAER/ESR team training sessions and workshops. By combining results from studies done by Forest Service and DOI agency personnel with research studies published since the initial reviews, we presented a comprehensive synthesis of seeding effectiveness knowledge that complements the review of other hillslope treatments published by other researchers. This information will help federal land managers make more cost-effective decisions on post-fire stabilization and rehabilitation treatments.

Report↗
USGS2016

Coastal bathymetry data collected in June 2014 from Fire Island, New York—The wilderness breach and shoreface

Scientists from the U.S. Geological Survey St. Petersburg Coastal and Marine Science Center in St. Petersburg, Florida, collected bathymetric data along the upper shoreface and within the wilderness breach at Fire Island, New York, in June 2014. The U.S. Geological Survey is involved in a post-Hurricane Sandy effort to map and monitor the morphologic evolution of the shoreface along Fire Island and model the evolution of the wilderness breach as a part of the Hurricane Sandy Supplemental Project GS2-2B. During this study, bathymetry was collected with single-beam echo sounders and global positioning systems, mounted to personal watercraft, along the Fire Island shoreface and within the wilderness breach. Additional bathymetry was collected using backpack global positioning systems along the flood shoals and shallow channels within the wilderness breach.

New York↗
USGS2017

Bathymetry data collected in October 2014 from Fire Island, New York—The wilderness breach, shoreface, and bay

Scientists from the U.S. Geological Survey St. Petersburg Coastal and Marine Science Center in St. Petersburg, Florida, conducted a bathymetric survey of Fire Island, New York, from October 5 to 10, 2014. The U.S. Geological Survey is involved in a post-Hurricane Sandy effort to map and monitor the morphologic evolution of the wilderness breach, which formed in October 2012 during Hurricane Sandy, as part of the Hurricane Sandy Supplemental Project GS2-2B. During this study, bathymetry data were collected, using single-beam echo sounders and global positioning systems mounted to personal watercraft, along the Fire Island shoreface and within the wilderness breach, Fire Island Inlet, Narrow Bay, and Great South Bay east of Nicoll Bay. Additional bathymetry and elevation data were collected using backpack and wheel-mounted global positioning systems along the subaerial beach (foreshore and backshore), flood shoals, and shallow channels within the wilderness breach and adjacent shoreface.

New York↗
USGS2015

Hurricane Sandy beach response and recovery at Fire Island, New York: Shoreline and beach profile data, October 2012 to October 2014

In response to the forecasted impact of Hurricane Sandy, which made landfall on October 29, 2012, the U.S. Geological Survey (USGS) began a substantial data-collection effort to assess the morphological impacts to the beach and dune system at Fire Island, New York. Global positioning system (GPS) field surveys of the beach and dunes were conducted just prior to and after landfall and these data were used to quantify change in several focus areas. In order to quantify morphologic change along the entire length of the island, pre-storm (May 2012) and post-storm (November 2012) lidar and aerial photography were used to assess changes to the shoreline and beach. As part of the USGS Hurricane Sandy Supplemental Fire Island Study, the beach is monitored periodically to enable better understanding of post-Sandy recovery. The alongshore state of the beach is recorded using a differential global positioning system (DGPS) to collect data around the mean high water (MHW; 0.46 meter North American Vertical Datum of 1988) to derive a shoreline, and the cross-shore response and recovery are measured along a series of 10 profiles. Overall, Hurricane Sandy substantially altered the morphology of Fire Island. However, the coastal system rapidly began to recover after the 2012­–13 winter storm season and continues to recover in the form of volume gains and shoreline adjustment.

New York↗
USGS2000

Fire ecology in the southeastern United States

Fire has played an important role in the structure of natural ecosystems throughout North America. As a natural process, fire helps clear away dead and dying plant matter and increases the production of native species that occur in fire prone habitats. It also reduces the invasion of exotic species and the succession to woody species in pitcher plant bogs, pine savannas, coastal prairies, marshes, and other natural plant communities of the southeastern United States.

Fact Sheet↗
USGS2012

Wildfire effects on source-water quality--Lessons from Fourmile Canyon fire, Colorado, and implications for drinking-water treatment

Forested watersheds provide high-quality source water for many communities in the western United States. These watersheds are vulnerable to wildfires, and wildfire size, fire severity, and length of fire season have increased since the middle 1980s (Westerling and others, 2006). Burned watersheds are prone to increased flooding and erosion, which can impair water-supply reservoirs, water quality, and drinking-water treatment processes. Limited information exists on the degree, timing, and duration of the effects of wildfire on water quality, making it difficult for drinking-water providers to evaluate the risk and develop management options. In order to evaluate the effects of wildfire on water quality and downstream ecosystems in the Colorado Front Range, the U.S. Geological Survey initiated a study after the 2010 Fourmile Canyon fire near Boulder, Colorado. Hydrologists frequently sampled Fourmile Creek at monitoring sites upstream and downstream of the burned area to study water-quality changes during hydrologic conditions such as base flow, spring snowmelt, and summer thunderstorms. This fact sheet summarizes principal findings from the first year of research. Stream discharge and nitrate concentrations increased downstream of the burned area during snowmelt runoff, but increases were probably within the treatment capacity of most drinking-water plants, and limited changes were observed in downstream ecosystems. During and after high-intensity thunderstorms, however, turbidity, dissolved organic carbon, nitrate, and some metals increased by 1 to 4 orders of magnitude within and downstream of the burned area. Increases of such magnitude can pose problems for water-supply reservoirs, drinking-water treatment plants, and downstream aquatic ecosystems.

Colorado↗
USGS2004

Coastal vulnerability assessment of Fire Island National Seashore to sea-level rise

A coastal vulnerability index (CVI) was used to map the relative vulnerability of the coast to future sea-level rise within Fire Island National Seashore (FIIS), New York. The CVI ranks the following in terms of their physical contribution to sea-level rise-related coastal change: geomorphology, regional coastal slope, rate of relative sea-level rise, shoreline change rates, mean tidal range and mean wave height. The rankings for each variable were combined and an index value calculated for 1-minute grid cells covering the park. The CVI highlights those regions where the physical effects of sea-level rise might be the greatest. This approach combines the coastal system's susceptibility to change with its natural ability to adapt to changing environmental conditions, yielding a quantitative, although relative, measure of the park's natural vulnerability to the effects of sea-level rise. Fire Island consists of stable and washover dominated portions of barrier beach backed by lagoons, tidal wetlands and marsh. The areas most vulnerable to sea-level rise are those with the highest historic occurrence of overwash and the highest rates of shoreline change. Implementation of large-scale beach nourishment and other coastal engineering alternatives being considered for Fire Island could alter the CVI computed here. The CVI provides an objective technique for evaluation and long-term planning by scientists and park managers.

New York↗
USGS2004

Emergency assessment of debris-flow hazards from basins burned by the Cedar and Paradise Fires of 2003, southern California

These maps present preliminary assessments of the probability of debris-flow activity and estimates of peak discharges that can potentially be generated by debris flows issuing from basins burned by the Cedar and Paradise Fires of October 2003 in southern California in response to 25-year, 10-year, and 2-year recurrence, 1-hour duration rain storms. The probability maps are based on the application of a logistic multiple regression model that describes the percent chance of debris-flow production from an individual basin as a function of burned extent, soil properties, basin gradients, and storm rainfall. The peak-discharge maps are based on application of a multiple-regression model that can be used to estimate debris-flow peak discharge at a basin outlet as a function of basin gradient, burn extent, and storm rainfall. Probabilities of debris-flow occurrence for the Cedar Fire range between 0 and 98% and estimates of debris-flow peak discharges range between 893 and 5,987 ft3/s (25 to 170 m3/s). Basins burned by the Paradise Fire show probabilities for debris-flow occurrence between 2 and 98%, and peak discharge estimates between 1,814 and 5,980 ft3/s (51 and 169 m3/s). These maps are intended to identify those basins that are most prone to the largest debris-flow events and provide information for the preliminary design of mitigation measures and for the planning of evacuation timing and routes.

Open-File Report↗
USGS2018

VS30 at three strong-motion recording stations in Napa and Napa County, California — Main Street in downtown Napa, Napa fire station number 3, and Kreuzer Lane — Calculations determined from s-wave refraction tomography and multichannel analysis of surface waves (Rayleigh and Love)

The August 24, 2014, moment magnitude ( M w ) 6.0 South Napa earthquake caused an estimated $400 million in structural damage to the City of Napa, California. In 2015, we acquired high-resolution P- and S-wave seismic data near three strong-motion recording stations in Napa County where high peak ground accelerations (PGAs) were recorded during the South Napa earthquake. In this report, we present results from three sites—Main Street in Downtown Napa (Northern California Seismic Network station, NCSN N016), Napa Fire Station Number 3 (National Strong Motion Project station, NSMP 1765), and Kreuzer Lane (station KRE, temporary deployment). To characterize the recording sites in terms of shallow-depth shear-wave velocities ( V S ), we used both surface waves (Rayleigh and Love) and body waves (S-wave) to evaluate the time-averaged V S in the upper 30 meters of the subsurface ( V S30 ). We used two-dimensional multichannel analysis of surface waves (MASW) to evaluate V S from the surface waves, and a refraction tomography inversion algorithm, developed by Hole in 1992, to evaluate V S from the body waves. As determined by the various methods, we found V S30 near the strong-motion recording stations on Main Street in Downtown Napa, Napa Fire Station Number 3, and on Kreuzer Lane to be from 281 meters per second (m/s) to 286 m/s, 297 to 371 m/s, and 885 to 916 m/s, respectively. The V S30 calculated from Love waves were slightly lower (10 m/s) than those calculated from Rayleigh waves at the Downtown Napa location and at Napa Fire Station Number 3 (4 m/s); however, V S30 calculated from Love waves was higher (190 m/s) than those calculated from Rayleigh waves at Kreuzer Lane. We also found that V S30 determined from MASW for both Love and Rayleigh waves varied depending on the number of shots along the profiles, and V S30 was not systematic based on the number of shots used in the analysis. Furthermore, V S30 calculated from S-wave refraction tomography are closer to those determined from MASW calculated from Love waves than from using Rayleigh waves.

California↗
USGS2018

VS30 at three strong-motion recording stations in Napa and Solano Counties, California — Lovall Valley Road, Broadway Street and Sereno Drive in Vallejo, and Vallejo Fire Station — Calculations determined from S-wave refraction tomography and multichannel analysis of surface waves (Rayleigh and Love)

The August 24, 2014, moment magnitude ( M w ) 6.0 South Napa earthquake caused an estimated $400 million in structural damage to the City of Napa, California. In 2015, we acquired high-resolution P- and S-wave seismic data near three strong-motion recording stations in Napa and Solano Counties where high peak ground accelerations (PGAs) were recorded during the South Napa earthquake. In this report, we present results from three sites—Lovall Valley Loop Road in Napa County (Northern California Seismic Network station, NCSN N019B) and Broadway Street and Sereno Drive (California Geological Survey station, CGS 68294) and Vallejo Fire Station (National Strong Motion Project station, NSMP 1759) in the City of Vallejo, California. To characterize the recording sites in terms of shallow-depth, shear-wave velocities ( V S ), we used both surface waves (Rayleigh and Love) and body waves (S-wave) to evaluate the time-averaged V S in the upper 30 meters of the subsurface ( V S30 ). We used two-dimensional (2D) multichannel analysis of surface waves (MASW) to evaluate V S from surface waves, and a refraction tomography inversion algorithm, developed by Hole in 1992, to evaluate V S from the body waves. As determined by the tomography and MASW analysis for Love waves, we found V S30 near the strong-motion recording stations at Lovall Valley Loop Road, Broadway Street and Sereno Drive, and the Vallejo Fire Station to be from 711 meters per second (m/s) to 767 m/s, 455 to 673 m/s, and 490 to 583 m/s, respectively. We found that V S30 determined from Love waves were higher than those determined from Rayleigh waves at the Lovall Valley Loop Road recording site (221 m/s higher) and at the Vallejo Fire Station site (62 and 48 m/s higher); however, V S30 from Love waves was lower than those from Rayleigh waves at the Broadway Street and Sereno Drive site (78 m/s lower). We also found that V S30 varied depending on the number of shot points used in our MASW analysis for both Love and Rayleigh waves. Furthermore, V S30 values determined from S-wave refraction tomography are generally closer to those determined from MASW using Love waves than those determined using Rayleigh waves.

California↗
USGS1997

Evaluation of the potential for debris and hyperconcentrated flows in Capulin Canyon as a result of the 1996 Dome fire, Bandelier National Monument, New Mexico

The Dome fire of April 1996 burned 6684 ha in Bandelier National Monument and the adjacent Sante Fe National Forest. The potential for significant debris- and hyperconcentrated-flow activity in Capulin Canyon is evaluated through 1) a systematic consideration of geologic and geomorphic factors that characterize the condition of the hillslope materials and channels following the fire, 2) examination of sedimentologic evidence for past debris-flow activity in the canyon, and 3) evaluation of the response of the watershed through the 1996 summer monsoon season. The lack of accumulations of dry-ravel material on the hillslopes or in channels, the absence of a continuous hydrophobic layer, the relatively intact condition of the riparian vegetation and of the fibrous root mat on the hillslopes, and the lack of evidence of widespread past debris- and hyperconcentrated-flow activity, even with evidence of past fires, indicate a low potential for debris-flow activity in Capulin Canyon. In addition, thunderstorms during the summer monsoon of 1996 resulted in abundant surface overland flow on the hillslopes which transported low-density pumice, charcoal, ash and some mineral soil downslope as small-scale and non-erosive debris flows. In some places cobble- and boulder-sized material was moved short distances. A moderate potential for debris- and hyperconcentrated-flow activity is identified for the two major tributary canyons to Capulin Canyon based on evidence of both summer of 1996 and possible historic significant debris-flow activity.

Open-File Report↗