scholarly journals Past and Present Vulnerability of Closed-Canopy Temperate Forests to Altered Fire Regimes: A Comparison of the Pacific Northwest, New Zealand, and Patagonia

BioScience ◽  
2014 ◽  
Vol 65 (2) ◽  
pp. 151-163 ◽  
Author(s):  
Cathy Whitlock ◽  
David B. McWethy ◽  
Alan J. Tepley ◽  
Thomas T. Veblen ◽  
Andrés Holz ◽  
...  
Keyword(s):  
New Zealand ◽  
Pacific Northwest ◽  
Temperate Forests ◽  
Fire Regimes ◽  
The Pacific ◽  
Closed Canopy

scholarly journals Toward a better understanding of climate and human impacts on late Holocene fire regimes in the Pacific Northwest, USA

2018 ◽  
Vol 42 (4) ◽  
pp. 478-512 ◽  
Author(s):  
Megan K Walsh ◽  
Haley J Duke ◽  
Kevin C Haydon
Keyword(s):  
Pacific Northwest ◽  
Ponderosa Pine ◽  
Late Holocene ◽  
Human Impacts ◽  
Fire Severity ◽  
Fire Regimes ◽  
The Past ◽  
The Pacific ◽  
Clackamas County ◽  
Study Sites

In order to fully appreciate the role that fire, both natural and anthropogenic, had in shaping pre-Euro-American settlement landscapes in the Pacific Northwest (PNW), it is necessary to develop a more robust method of evaluating paleofire reconstructions. Here we demonstrate an approach that includes the identification of charcoal morphotypes (i.e. visually distinct charcoal particles), and incorporates both paleoecological and archaeological data sets, to more specifically determine both the nature of past fire regimes (i.e. fuel type and fire severity) and the likely ignition source of those fires. We demonstrate the usefulness of this approach by reconstructing the late Holocene fire and vegetation histories of Lake Oswego (Clackamas County), Oregon, and Fish Lake (Okanogan County), Washington, using macroscopic charcoal and pollen analysis of sediment cores. The histories were compared with climatic records from the PNW as well as archaeological, ethnographic, and historical records from the Lower Columbia River Valley and Southern Columbia Plateau cultural regions. Our results indicate that while centennial-to-millennial-scale climate change had limited influence on the fire regimes at the study sites during the past ∼3800 years, the use of fire by Native Americans for a variety of reasons, particularly after ca. 1200 calendar years before present (AD 750), had a far greater impact. Charcoal morphotype ratios also indicate that fires in the two watersheds were fundamentally different in their severity and impact, and led to major shifts in the forests and woodlands surrounding Lake Oswego, but helped maintain the ponderosa pine-dominated forest at Fish Lake. The elimination of fire from the two study sites during the past 100–300 years is likely the combined result of Euro-American contact and the arrival of disease in the PNW, as well as 20th-century fire suppression and grazing effects on fuel continuity, which has implications for future forest management and restoration efforts in the PNW.

Why is the productivity of Douglas-fir higher in New Zealand than in its native range in the Pacific Northwest, USA?

2008 ◽  
Vol 255 (12) ◽  
pp. 4040-4046 ◽  
Author(s):  
Richard Waring ◽  
Alan Nordmeyer ◽  
David Whitehead ◽  
John Hunt ◽  
Michael Newton ◽  
...  
Keyword(s):  
New Zealand ◽  
Pacific Northwest ◽  
Douglas Fir ◽  
Native Range ◽  
The Pacific

scholarly journals Closed Canopies Crowd Out Bats: Planning Artificial Gap Creation

2021 ◽  
Author(s):  
◽  
Alana Simmons ◽  
Keyword(s):  
Pacific Northwest ◽  
Habitat Diversity ◽  
Weighted Overlay ◽  
Bat Activity ◽  
The Pacific ◽  
Closed Canopy ◽  
Management Recommendations ◽  
Northwest Region ◽  
Gap Creation ◽  
Forest Managers

Managed even-aged forest stands often lack small to medium-sized canopy gaps that help to increase habitat diversity and, in turn, wildlife diversity. A large body of literature suggests that this habitat diversity is especially important for bat communities and that bat activity and diversity can be depressed in closed canopy, even-aged stands. Open- and edge-adapted bats have evolved specific wing morphologies and echolocation call structures that make them reliant upon forest gaps as energy efficient foraging grounds in otherwise structurally cluttered forests. Artificial gap creation projects that increase habitat diversity have been implemented to benefit ungulates, and a similar approach could also be applied to support foraging activity of bats in even-aged forests that lack dynamic natural disturbances. However, little consideration has been given to the use of gaps by bats and no comprehensive approach for artificial gap creation for the benefit of bats has been proposed. In response to this lack of guidance for forest managers in the Pacific Northwest region, this document provides a focused review of existing literature regarding bats and gaps. This information was used to create specific management recommendations regarding physical characteristics of gaps and their spatial context on the landscape. To identify ideal locations for gap creation on the ground according to these recommendations, a weighted overlay method is suggested. This document has been written for the use of forest managers throughout the entire Pacific Northwest region. However, the Siuslaw National Forest (NF), a Late-Successional Reserve on the coast of Oregon, was used as a specific case study to demonstrate how the proposed approach can be applied to a specific management unit. The document is broken into the four following chapters. Chapter 1 introduces the Siuslaw NF and briefly describes the forest’s bat community, major vegetation zones, forest succession, disturbance regime, and management. Using previous research from the region as a guide, Chapter 2 provides background information regarding bat biology and ecology and it details the importance of gaps, forest edges, and interior stands as habitat for forest-dwelling bats. Different types of forest gaps common to the Pacific Northwest are discussed including both artificially created and naturally occurring gaps. Chapter 3, again guided by review of existing literature, highlights important gap parameters including physical characteristics and spatial context to promote bat activity as well as provides specific gap management recommendations. Chapter 4 provides an example of how to input management recommendations into a Geographic Information System (GIS) to pinpoint ideal locations for gap creation within a management unit. A weighted overlay analysis, a common GIS tool, was conducted in the Siuslaw NF following the management guidelines, and resulting maps are discussed. The ultimate goal of this document is to provide forest managers in the Pacific Northwest region with the knowledge and planning tools necessary to promote foraging activity of specialized open- and edge-adapted species. While other management units may have different or additional managerial constraints than those of the Siuslaw NF, thIS proposed approach can be easily adapted to meet the varied needs of different forests. By following this approach, forest managers can provide the habitat diversity and complexity necessary to promote high levels of bat activity and diversity within even-aged, closed canopy forests.

scholarly journals Changing wildfire, changing forests: the effects of climate change on fire regimes and vegetation in the Pacific Northwest, USA

Fire Ecology ◽  
2020 ◽  
Vol 16 (1) ◽  
Author(s):  
Jessica E. Halofsky ◽  
David L. Peterson ◽  
Brian J. Harvey
Keyword(s):  
Pacific Northwest ◽  
Fire Regimes ◽  
Tree Regeneration ◽  
Ecosystem Change ◽  
Fire Intensity ◽  
Future Research ◽  
Fuel Treatments ◽  
Warming Climate ◽  
Resource Managers ◽  
The Pacific

Abstract Background Wildfires in the Pacific Northwest (Washington, Oregon, Idaho, and western Montana, USA) have been immense in recent years, capturing the attention of resource managers, fire scientists, and the general public. This paper synthesizes understanding of the potential effects of changing climate and fire regimes on Pacific Northwest forests, including effects on disturbance and stress interactions, forest structure and composition, and post-fire ecological processes. We frame this information in a risk assessment context, and conclude with management implications and future research needs. Results Large and severe fires in the Pacific Northwest are associated with warm and dry conditions, and such conditions will likely occur with increasing frequency in a warming climate. According to projections based on historical records, current trends, and simulation modeling, protracted warmer and drier conditions will drive lower fuel moisture and longer fire seasons in the future, likely increasing the frequency and extent of fires compared to the twentieth century. Interactions between fire and other disturbances, such as drought and insect outbreaks, are likely to be the primary drivers of ecosystem change in a warming climate. Reburns are also likely to occur more frequently with warming and drought, with potential effects on tree regeneration and species composition. Hotter, drier sites may be particularly at risk for regeneration failures. Conclusion Resource managers will likely be unable to affect the total area burned by fire, as this trend is driven strongly by climate. However, fuel treatments, when implemented in a spatially strategic manner, can help to decrease fire intensity and severity and improve forest resilience to fire, insects, and drought. Where fuel treatments are less effective (wetter, high-elevation, and coastal forests), managers may consider implementing fuel breaks around high-value resources. When and where post-fire planting is an option, planting different genetic stock than has been used in the past may increase seedling survival. Planting seedlings on cooler, wetter microsites may also help to increase survival. In the driest topographic locations, managers may need to consider where they will try to forestall change and where they will allow conversions to vegetation other than what is currently dominant.

scholarly journals Contrasting the Pathogen Loads in Co-Existing Populations of Phytophthora pluvialis and Nothophaeocryptopus gaeumannii in Douglas Fir Plantations in New Zealand and the Pacific Northwest United States

2019 ◽  
Vol 109 (11) ◽  
pp. 1908-1921 ◽  
Author(s):  
Mireia Gómez-Gallego ◽  
Jared M. LeBoldus ◽  
Martin Karl-Friedrich Bader ◽  
Everett Hansen ◽  
Lloyd Donaldson ◽  
...  
Keyword(s):  
United States ◽  
New Zealand ◽  
Pacific Northwest ◽  
Spatial Scales ◽  
Douglas Fir ◽  
The Pacific ◽  
Foliar Pathogen ◽  
Swiss Needle Cast ◽  
Phytophthora Pluvialis ◽  
Foliar Pathogens

The emergence of Phytophthora pluvialis as a foliar pathogen of Douglas fir in New Zealand and the Pacific Northwest United States has raised questions about its interaction with the widespread Swiss needle cast (SNC) disease. During Spring 2017, we repeatedly sampled 30 trees along an environmental gradient in each region and 292 additional trees in a longitudinal transect to assess the P. pluvialis epidemic and the association between P. pluvialis and Nothophaeocryptopus gaeumannii, which are causal agents of SNC. Both pathogens were consistently more abundant in the host’s exotic environment in New Zealand. In both areas, the two pathogens co-exist in different spatial scales for regions and needles. The relative abundance of both pathogens was negatively correlated in the Pacific Northwest, where both presumably have co-existed for longer. Our findings confirmed the interaction of P. pluvialis and N. gaeumannii as foliar pathogens of Douglas fir and suggest a within-site spatial variation in the Pacific Northwest.

scholarly journals Phytophthora pluvialis Studies on Douglas-fir Require Swiss Needle Cast Suppression

Plant Disease ◽  
2017 ◽  
Vol 101 (7) ◽  
pp. 1259-1262 ◽  
Author(s):  
Mireia Gómez-Gallego ◽  
Martin Karl-Friedrich Bader ◽  
Peter Matthew Scott ◽  
Sebastian Leuzinger ◽  
Nari Michelle Williams
Keyword(s):  
New Zealand ◽  
Pacific Northwest ◽  
Radiata Pine ◽  
Douglas Fir ◽  
Needle Cast ◽  
The Pacific ◽  
Swiss Needle Cast ◽  
Phytophthora Pluvialis ◽  
Red Needle Cast ◽  
Ubiquitous Presence

Phytophthora pluvialis is associated with early defoliation and shoot dieback in Douglas-fir in Oregon and New Zealand. In 2013, P. pluvialis was described from mixed tanoak-Douglas-fir forests in the Pacific Northwest and concurrently recognized as the main causal agent of red needle cast (RNC) in New Zealand radiata pine plantations. Little is known about its infection cycle and impact on host physiology. P. pluvialis studies in Douglas-fir are challenging due to the ubiquitous presence of the endophyte Phaeocryptopus gaeumannii, which produces similar symptoms and premature defoliation with persistent needle wetness, known as Swiss needle cast (SNC). Nonetheless, our study showed P. pluvialis infection in the presence of SNC. Exclusive expression of P. pluvialis is difficult to achieve as both diseases are promoted by high humidity. Here we established a ‘dry leaf’ strategy to suppress SNC when inoculating Douglas-fir needles for RNC studies. Sheltering plants along with drip irrigation to avoid needle wetness during the P. gaeumannii sporulation period suppressed its development in the new season flush. The diminished endophyte inoculum enabled bias-reduced studies of P. pluvialis impacts on Douglas-fir without the confounding effects of stomatal blockage and premature defoliation caused by P. gaeumannii.

scholarly journals Tools for Assessing Climate Impacts on Fish and Wildlife

2013 ◽  
Vol 4 (1) ◽  
pp. 220-241 ◽  
Author(s):  
Chad B. Wilsey ◽  
Joshua J. Lawler ◽  
Edwin P. Maurer ◽  
Donald McKenzie ◽  
Patricia A. Townsend ◽  
...  
Keyword(s):  
Climate Change ◽  
Pacific Northwest ◽  
Puget Sound ◽  
Fire Regimes ◽  
Climate Impacts ◽  
Wildlife Habitat ◽  
Individual Species ◽  
Willamette Valley ◽  
The Pacific ◽  
Georgia Basin

Abstract Climate change is already affecting many fish and wildlife populations. Managing these populations requires an understanding of the nature, magnitude, and distribution of current and future climate impacts. Scientists and managers have at their disposal a wide array of models for projecting climate impacts that can be used to build such an understanding. Here, we provide a broad overview of the types of models available for forecasting the effects of climate change on key processes that affect fish and wildlife habitat (hydrology, fire, and vegetation), as well as on individual species distributions and populations. We present a framework for how climate-impacts modeling can be used to address management concerns, providing examples of model-based assessments of climate impacts on salmon populations in the Pacific Northwest, fire regimes in the boreal region of Canada, prairies and savannas in the Willamette Valley-Puget Sound Trough-Georgia Basin ecoregion, and marten Martes americana populations in the northeastern United States and southeastern Canada. We also highlight some key limitations of these models and discuss how such limitations should be managed. We conclude with a general discussion of how these models can be integrated into fish and wildlife management.

scholarly journals Recent Trends in Large Hardwoods in the Pacific Northwest, USA

Forests ◽  
2018 ◽  
Vol 9 (10) ◽  
pp. 651 ◽  
Author(s):  
Jonathan Long ◽  
Andrew Gray ◽  
Frank Lake
Keyword(s):  
Pacific Northwest ◽  
Basal Area ◽  
Fire Regimes ◽  
Private Land ◽  
Mature Trees ◽  
Hardwood Trees ◽  
The Pacific ◽  
Large Trees ◽  
Recent Trends ◽  
Time Periods

Forest densification, wildfires, and disease can reduce the growth and survival of hardwood trees that are important for biological and cultural diversity within the Pacific Northwest of USA. Large, full-crowned hardwoods that produce fruit and that form large cavities used by wildlife were sustained by frequent, low-severity fires prior to Euro-American colonization. Shifts in fire regimes and other threats could be causing declines in, large hardwood trees. To better understand whether and where such declines might be occurring, we evaluated recent trends in Forest Inventory and Analysis (FIA) data from 1991–2016 in California and southern Oregon. We included plots that lay within areas of frequent fire regimes during pre-colonial times and potential forest habitats for fisher, a rare mammal that depends on large live hardwoods. We analyzed changes in basal area for eight hardwood species, both overall and within size classes, over three time periods within ecoregions, and in public and private land ownerships. We found the basal area to generally be stable or increasing for these species. However, data for California black oak suggested a slight decline in basal area overall, and among both very large trees and understory trees; that decline was associated with fire mortality on national forest lands. In addition, mature trees with full crowns appeared to sharply decline across all species. Many trends were not statistically significant due to high variation, especially since more precise data from remeasured trees were only available for the two most recent time periods. Continued analysis of these indicators using remeasured trees will help to evaluate whether conservation efforts are sustaining large, full-crowned trees and their associated benefits.

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