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Lan YH, Shaw DC, Lee EH, Beedlow PA. Distribution of a Foliage Disease Fungus Within Canopies of Mature Douglas-Fir in Western Oregon. FRONTIERS IN FORESTS AND GLOBAL CHANGE 2022; 5:1-15. [PMID: 36278245 PMCID: PMC9580348 DOI: 10.3389/ffgc.2022.743039] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Nothophaeocryptopus gaeumannii is a common native, endophytic fungus of Douglas-fir foliage, which causes Swiss needle cast, an important foliage disease that is considered a threat to Douglas-fir plantations in Oregon. Disease expression is influenced by fungal fruiting bodies (pseudothecia), which plug the stomata and inhibit gas exchange. Trees are impacted when pseudothecia plug stomates on 1-year-old and older needles resulting in early needle abscission. Mature (100 years+) trees appear to be less impacted from disease, and we hypothesize this is due to the greater emergence of pseudothecia on older than younger needles, which allows for more needle retention. We measured the density of pseudothecia occluding stomates across 2- to 5-year-old needles from upper, middle, and lower canopy positions of mature trees at three sites in the Oregon Coast Range and two sites in the western Oregon Cascade Mountains. Binomial generalized linear mixed model (GLMM) was used to test for the effects of canopy position (upper, middle, and lower), sites, needle age (2-5 years old), and years (2016 and 2017), and their interactions on the pseudothecia density. Pseudothecia density varied annually depending on sites, needle age and canopy positions. Pseudothecia density peaked on 3-, and 4-year-old needles, however, needles emerging from the same year, like 2-year-old needles in 2016 and 3-year-old needles in 2017 both emerged in 2014, had consistently similar patterns of pseudothecia density for both years, across site and canopy positions. Canopy position was important for 3-, and 4-year-old needles, showing less pseudothecia in the lower canopy. This research confirms that N. gaeumannii pseudothecia density is greatest in 3- and 4-year old needles in mature trees in contrast to plantations where pseudothecia density usually peaks on 2-year-old needles, and that pseudothecia density (disease severity) is generally lower in mature trees. Something about mature forest canopies and foliage appears to increase the time it takes for pseudothecia to emerge from the needles, in contrast to younger plantations, thus allowing the mature trees to have greater needle retention.
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Affiliation(s)
- Yung-Hsiang Lan
- Department of Forest Engineering, Resources, and Management, Oregon State University, Corvallis, OR, United States
- Correspondence: Yung-Hsiang Lan,
| | - David C. Shaw
- Department of Forest Engineering, Resources, and Management, Oregon State University, Corvallis, OR, United States
| | - E. Henry Lee
- U.S. Environmental Protection Agency, Pacific Ecological Systems Division, Corvallis, OR, United States
| | - Peter A. Beedlow
- U.S. Environmental Protection Agency, Pacific Ecological Systems Division, Corvallis, OR, United States
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Moriarty KM, Thompson J, Delheimer M, Barry BR, Linnell M, Levi T, Hamm K, Early D, Gamblin H, Szykman Gunther M, Ellison J, Prevéy JS, Hartman J, Davis R. Predicted distribution of a rare and understudied forest carnivore: Humboldt marten ( Martes caurina humboldtensis). PeerJ 2021; 9:e11670. [PMID: 34434640 PMCID: PMC8354145 DOI: 10.7717/peerj.11670] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 06/03/2021] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND Many mammalian species have experienced range contractions. Following a reduction in distribution that has resulted in apparently small and disjunct populations, the Humboldt marten (Martes caurina humboldtensis) was recently designated as federally Threatened and state Endangered. This subspecies of Pacific marten occurring in coastal Oregon and northern California, also known as coastal martens, appear unlike martens that occur in snow-associated regions in that vegetation associations appear to differ widely between Humboldt marten populations. We expected current distributions represent realized niches, but estimating factors associated with long-term occurrence was challenging for this rare and little-known species. Here, we assessed the predicted contemporary distribution of Humboldt martens and interpret our findings as hypotheses correlated with the subspecies' niche to inform strategic conservation actions. METHODS We modeled Humboldt marten distribution using a maximum entropy (Maxent) approach. We spatially-thinned 10,229 marten locations collected from 1996-2020 by applying a minimum distance of 500-m between locations, resulting in 384 locations used to assess correlations of marten occurrence with biotic and abiotic variables. We independently optimized the spatial scale of each variable and focused development of model variables on biotic associations (e.g., hypothesized relationships with forest conditions), given that abiotic factors such as precipitation are largely static and not alterable within a management context. RESULTS Humboldt marten locations were positively associated with increased shrub cover (salal (Gautheria shallon)), mast producing trees (e.g., tanoak, Notholithocarpus densiflorus), increased pine (Pinus sp.) proportion of total basal area, annual precipitation at home-range spatial scales, low and high amounts of canopy cover and slope, and cooler August temperatures. Unlike other recent literature, we found little evidence that Humboldt martens were associated with old-growth structural indices. This case study provides an example of how limited information on rare or lesser-known species can lead to differing interpretations, emphasizing the need for study-level replication in ecology. Humboldt marten conservation would benefit from continued survey effort to clarify range extent, population sizes, and fine-scale habitat use.
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Affiliation(s)
- Katie M. Moriarty
- Western Sustainable Forestry, National Council for Air and Stream Improvement, Inc., Corvallis, OR, United States of America
| | - Joel Thompson
- Pacific Northwest Region Data Resources Management, USDA Forest Service, Joseph, OR, United States of America
| | - Matthew Delheimer
- Pacific Southwest Research Station, USDA Forest Service, Placerville, CA, United States of America
| | - Brent R. Barry
- Confederated Tribes of the Grand Ronde, Grand Ronde, OR, United States of America
| | - Mark Linnell
- Pacific Northwest Research Station, USDA Forest Service, Corvallis, OR, United States of America
| | - Taal Levi
- Department of Fisheries and Wildlife, Oregon State University, Corvallis, OR, United States of America
| | - Keith Hamm
- Green Diamond Resource Company, Korbel, CA, United States of America
| | - Desiree Early
- Green Diamond Resource Company, Korbel, CA, United States of America
| | - Holly Gamblin
- Department of Wildlife, Humboldt State University, Arcata, CA, United States of America
| | | | - Jordan Ellison
- Western Sustainable Forestry, National Council for Air and Stream Improvement, Inc., Corvallis, OR, United States of America
| | - Janet S. Prevéy
- Fort Collins Science Center, US Geological Survey, Fort Collins, CO, United States of America
| | | | - Raymond Davis
- Pacific Northwest Region, USDA Forest Service, Corvallis, OR, United States of America
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Hazards of Risk: Identifying Plausible Community Wildfire Disasters in Low-Frequency Fire Regimes. FORESTS 2021. [DOI: 10.3390/f12070934] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Optimized wildfire risk reduction strategies are generally not resilient in the event of unanticipated, or very rare events, presenting a hazard in risk assessments which otherwise rely on actuarial, mean-based statistics to characterize risk. This hazard of actuarial approaches to wildfire risk is perhaps particularly evident for infrequent fire regimes such as those in the temperate forests west of the Cascade Range crest in Oregon and Washington, USA (“Westside”), where fire return intervals often exceed 200 years but where fires can be extremely intense and devastating. In this study, we used wildfire simulations and building location data to evaluate community wildfire exposure and identify plausible disasters that are not based on typical mean-based statistical approaches. We compared the location and magnitude of simulated disasters to historical disasters (1984–2020) in order to characterize plausible surprises which could inform future wildfire risk reduction planning. Results indicate that nearly half of communities are vulnerable to a future disaster, that the magnitude of plausible disasters exceeds any recent historical events, and that ignitions on private land are most likely to result in very high community exposure. Our methods, in combination with more typical actuarial characterizations, provide a way to support investment in and communication with communities exposed to low-probability, high-consequence wildfires.
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Shaw DC, Ritóková G, Lan YH, Mainwaring DB, Russo A, Comeleo R, Navarro S, Norlander D, Smith B. Persistence of the Swiss Needle Cast Outbreak in Oregon Coastal Douglas-Fir and New Insights from Research and Monitoring. JOURNAL OF FORESTRY 2021; 119:407-421. [PMID: 35757814 PMCID: PMC9214664 DOI: 10.1093/jofore/fvab011] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Swiss needle cast (SNC), caused by Nothophaeocryptopus gaeumannii, is a foliage disease of Douglas-fir (Pseudotsuga menziesii), that reduces growth in native stands and exotic plantations worldwide. An outbreak of SNC began in coastal Oregon in the mid-1990s and has persisted since that time. Here we review the current state of knowledge after 24 years of research and monitoring, with a focus on Oregon, although the disease is significant in coastal Washington and has recently emerged in southwestern British Columbia. We present new insights into SNC distribution, landscape patterns, disease epidemiology and ecology, host-pathogen interactions, trophic and hydrologic influences, and the challenges of Douglas-fir plantation management in the presence of the disease. In Oregon, the SNC outbreak has remained geographically contained but has intensified. Finally, we consider the implications of climate change and other recently emerged foliage diseases on the future of Douglas-fir plantation management.
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Affiliation(s)
- David C. Shaw
- Department of Forest Engineering, Resources, and Management, Forestry and Natural Resources Extension, Oregon State University, Corvallis, OR, USA
| | - Gabriela Ritóková
- Department of Forest Engineering, Resources, and Management, Oregon State University, Corvallis, OR, USA
| | - Yung-Hsiang Lan
- Department of Forest Engineering, Resources, and Management, Oregon State University, Corvallis, OR, USA
| | - Doug B. Mainwaring
- Department of Forest Engineering, Resources, and Management, Oregon State University, Corvallis, OR, USA
| | - Andrew Russo
- Department of Forest Engineering, Resources, and Management, Oregon State University, Corvallis, OR, USA
| | - Randy Comeleo
- US Environmental Protection Agency, Corvallis, OR, USA
| | - Sarah Navarro
- USDA Forest Service, Region Six, State and Private Forestry, Forest Health Protection, Portland, OR, USA
| | | | - Ben Smith
- USDA Forest Service, Region Six, State and Private Forestry, Forest Health Protection, Sandy, OR, USA
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