scholarly journals Restoration Treatments Improve Overstory Tree Resistance Attributes and Growth in a Ponderosa Pine/Douglas-Fir Forest

Forests ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 574
Author(s):  
Justin S. Crotteau ◽  
Christopher R. Keyes
Keyword(s):  
Ponderosa Pine ◽  
Bark Beetles ◽  
Douglas Fir ◽  
Fuel Reduction ◽  
Surface Fire ◽  
Tree Resistance ◽  
Crown Length ◽  
Treatment Type ◽  
The Impact ◽  
Overstory Tree

Research Highlights: This study provides much needed insight into the development of resistance to disturbance and growth dynamics of overstory trees in response to restoration-based fuel reduction, and will be useful to scientists and managers attempting to better grasp the relative merits of restoration treatment types. Background and Objectives: Restoration-based fuel reduction treatments are common in dry, fire-prone forests of the western United States. The primary objective of such treatments is to immediately reduce a stand’s crown fire hazard. However, the impact of these treatments on residual trees is relevant to assess their longevity and resistance to future disturbances. In this study, we evaluate the effects of restoration on retained overstory ponderosa pine (Pinus ponderosa Lawson & C. Lawson) and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) trees in western Montana, where treatments were experimentally implemented 13 years prior as part of the national Fire and Fire Surrogate study. Materials and Methods: We examined tree attributes in response to the following replicated treatments: thin-only, burn-only, thin + burn, and a no-action control. We analyzed three different tree attributes that confer resistance to common disturbances: height-to-diameter ratio (resistance to wind), bark thickness (resistance to surface fire), and growth efficiency (resistance to bark beetles). Results: Our models suggest that thinning (with or without burning) alters tree attributes relative to the control in a manner that may increase tree resistance to wind and snow breakage, surface fire, and biotic agents such as bark beetles. Further analysis of annual growth of ponderosa pine and Douglas-fir varied by treatment type: thinning-based restoration (thin-only and thin + burn) increased diameter growth for both species, crown length and width in ponderosa pine, and crown length in Douglas-fir relative to unthinned treatments. Burning (burn-only and thin + burn) did not significantly affect tree growth relative to unburned treatments. Conclusions: While low-severity prescribed burning treatments are often used for restoration and have various ecosystem benefits, this study demonstrates that thinning (alone or in addition to burning) produces more measureable, beneficial results to overstory tree disturbance resistance metrics and growth.

A field experiment informs expected patterns of conifer regeneration after disturbance under changing climate conditions

2015 ◽  
Vol 45 (11) ◽  
pp. 1607-1616 ◽  
Author(s):  
Monica T. Rother ◽  
Thomas T. Veblen ◽  
Luke G. Furman
Keyword(s):  
Field Experiment ◽  
Pinus Ponderosa ◽  
Ponderosa Pine ◽  
Douglas Fir ◽  
Tree Regeneration ◽  
Colorado Front Range ◽  
Front Range ◽  
Average Growth ◽  
Growth And Survival ◽  
Treatment Type

Climate change may inhibit tree regeneration following disturbances such as wildfire, altering post-disturbance vegetation trajectories. We implemented a field experiment to examine the effects of manipulations of temperature and water on ponderosa pine (Pinus ponderosa Douglas ex P. Lawson & C. Lawson) and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings planted in a low-elevation, recently disturbed setting of the Colorado Front Range. We implemented four treatments: warmed only (Wm), watered only (Wt), warmed and watered (WmWt), and control (Co). We found that measures of growth and survival varied significantly by treatment type. Average growth and survival was highest in the Wt plots, followed by the Co, WmWt, and Wm plots, respectively. This general trend was observed for both conifer species, although average growth and survival was generally higher in ponderosa pine than in Douglas-fir. Our findings suggest that warming temperatures and associated drought are likely to inhibit post-disturbance regeneration of ponderosa pine and Douglas-fir in low-elevation forests of the Colorado Front Range and that future vegetation composition and structure may differ notably from historic patterns in some areas. Our findings are relevant to other forested ecosystems in which a warming climate may similarly inhibit regeneration by dominant tree species.

Fire effects on shoot growth characteristics of ponderosa pine in Colorado

1983 ◽  
Vol 13 (4) ◽  
pp. 620-625 ◽  
Author(s):  
James G. Wyant ◽  
Richard D. Laven ◽  
Philip N. Omi
Keyword(s):  
Ponderosa Pine ◽  
Shoot Growth ◽  
Fire Effects ◽  
Growth Characteristics ◽  
Growth Potential ◽  
Fire Damage ◽  
Fall Season ◽  
Surface Fire ◽  
Bud Formation ◽  
The Impact

The impact of fire damage on the shoot growth potential of 36 branches on each of nine ponderosa pine (Pinusponderosa Laws.) trees was evaluated after a fall season prescribed surface fire. In the first season after burning, mean fascicle lengths and bud sizes (length and diameter) were greater on trees which received underburning treatment than on unburned trees. No treatment effect was observed on shoot lengths, needle numbers, or fascicle numbers, characters determined in the season of bud formation.

The effects of mechanical fuel reduction treatments on the activity of bark beetles (Coleoptera: Scolytidae) infesting ponderosa pine

2006 ◽  
Vol 230 (1-3) ◽  
pp. 55-68 ◽  
Author(s):  
Christopher J. Fettig ◽  
Joel D. McMillin ◽  
John A. Anhold ◽  
Shakeeb M. Hamud ◽  
Robert R. Borys ◽  
...  
Keyword(s):  
Ponderosa Pine ◽  
Bark Beetles ◽  
Fuel Reduction

scholarly journals Influence of concurrence of extreme drought and heat events on carbon and energy fluxes in dominant ecosystems in the Pacific Northwest region

2018 ◽  
Author(s):  
Hyojung Kwon ◽  
Whitney Creason ◽  
Beverly E. Law ◽  
Christopher J. Still ◽  
Chad Hanson
Keyword(s):  
Heat Flux ◽  
Pacific Northwest ◽  
Latent Heat ◽  
Latent Heat Flux ◽  
Ponderosa Pine ◽  
Douglas Fir ◽  
Energy Fluxes ◽  
Extreme Climate ◽  
Climate Stress ◽  
The Impact

Abstract. The impacts of drought intensities and vapor pressure deficits (VPD) beyond historic norms in Pacific Northwest (PNW), USA, are critical in understanding the potential future function and resilience of ecosystems in the region. While ecosystems in this region are adapted to seasonal droughts, June 2015 temperatures were the highest recorded in the region and strongly coupled with relatively low soil moisture. June is usually the best month for growth in the PNW. Here, we examined the impact of the June 2015 climate extremes on carbon and energy fluxes at sagebrush in the high desert, young and mature ponderosa pine in the semi-arid Great Basin, and Douglas-fir in the mesic Coast Range ecoregion compared to an average climate year (2014). We assessed if the ecosystems recover from extreme climate stress within the growing season. The monthly anomalies in temperature and VPD were 3 standard deviations, and precipitation was 1 standard deviation, outside the 30-year mean at all sites. In sagebrush, the carry-over effect of precipitation (i.e., intensive precipitation prior to the drought and heat) mitigated the immediate impact of extreme climate stress, leading to 25–40 % increase in net ecosystem production (NEP) and gross primary production (GPP), with little change in ecosystem respiration (RE) and 65 % increase in latent heat flux, compared to the June 2014. The drought and heat lowered NEP by 35–65 % and GPP by 15–33 % in ponderosa pine and Douglas-fir. A greater increase in latent heat flux was observed in Douglas-fir (110 %) than in ponderosa pine (

scholarly journals JC Virus Seroprevalence and JCVAb Index in Polish Multiple Sclerosis Patients Treated with Immunomodulating or Immunosuppressive Therapies

2021 ◽  
Vol 10 (9) ◽  
pp. 1998
Author(s):  
Robert Bonek ◽  
Wojciech Guenter ◽  
Robert Jałowiński ◽  
Anna Karbicka ◽  
Anna Litwin ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Jc Virus ◽  
Dimethyl Fumarate ◽  
Risk Category ◽  
Seroprevalence Rate ◽  
Immunomodulatory Drugs ◽  
Cross Sectional ◽  
Treatment Type ◽  
Multiple Sclerosis Patients ◽  
The Impact

The use of a highly-effective treatment for multiple sclerosis (MS) is associated with a severe risk of developing complications, such as progressive multifocal leukoencephalopathy (PML) caused by the John Cunningham virus (JCV). The aim of this study was to evaluate the correlation between anti-JCV Ab seroprevalence, anti-JCV AI, demographic and clinical factors as well as the type of therapy used in the Polish MS population. This is a multicentre, prospective and cross-sectional study involving 1405 MS patients. The seroprevalence of anti-JCV Ab and anti-JCV AI levels as well as AI categories were analysed with the use of a second-generation two-step ELISA test (STRATIFY JCV DxSelect). The overall prevalence of anti-JCV Ab was 65.8%. It was shown that seroprevalence increases with the patient’s age. The seroprevalence was significantly associated with the treatment type, and the highest values (76%) were obtained from immunosuppressant-treated patients. Overall, 63.3% of seropositive patients had an antibody index (AI) level of >1.5. In the seropositive patient group, the mean AI level amounted to 2.09. Similarly to the seroprevalence, AI levels correlated with the patient’s age; AI level for patients above 40 years old and from subsequent age quintiles plateaued, amounting to at least 1.55. Patients treated with immunosuppressants and immunomodulatory drugs obtained the highest (1.67) and lowest (1.35) AI levels, respectively. Of the immunosuppressants used, the highest mean AI levels were observed in mitoxantrone and cladribine groups, amounting to 1.75 and 1.69, respectively. In patients treated with immunomodulatory drugs, the lowest AI levels were observed in the dimethyl fumarate (DMF) group (1.11). The seroprevalence rate in the Polish MS population is one of the highest in Europe. The majority of seropositive patients had an anti-JCV Ab level qualifying them for a high-risk category. The highest mean AI levels are observed in patients receiving immunosuppressants, especially mitoxantrone and cladribine. Patients receiving immunomodulatory drugs have lower AI levels compared to treatment-naïve subjects, especially when treated with DMF. Further studies, especially longitudinal studies, are required to determine the impact of MS drugs on the seroprevalence of anti-JCV Ab and AI levels.

INFESTATION OF CERATOCYSTIS WAGENERI-INFECTED PONDEROSA PINES BY BARK BEETLES (COLEOPTERA: SCOLYTIDAE) IN THE CENTRAL SIERRA NEVADA

1980 ◽  
Vol 112 (7) ◽  
pp. 725-730 ◽  
Author(s):  
D. J. Goheen ◽  
F. W. Cobb
Keyword(s):  
Sierra Nevada ◽  
Bark Beetle ◽  
Ponderosa Pine ◽  
Bark Beetles ◽  
Dendroctonus Brevicomis ◽  
Disease Category ◽  
The Relationship ◽  
Periodic Examination ◽  
Apparently Healthy

AbstractThe relationship between bark beetle infestation of ponderosa pine and severity of infection by Ceratocystis wageneri was investigated by closely monitoring 256 trees (136 apparently healthy, 60 moderately diseased, and 60 severely diseased at initiation of study) for beetle infestation from summer 1972 to fall 1975. Disease ratings were updated by periodic examination, and some trees changed disease category during the study. Ninety trees were infested by Dendroctonus brevicomis, D. ponderosae, or both, five by buprestids alone, and one tree died from effects of the pathogen alone. Sixty-two of the beetle-infested trees were severely diseased at time of infestation, 25 were moderately diseased, and only three were apparently healthy. Thus, the results showed that bark beetles were much more likely to infest infected than healthy trees. Among diseased trees, those with advanced infections were most likely to be infested. There was evidence that buprestids (especially Melanophila spp.) and possibly Ips spp. attacked diseased trees prior to Dendroctonus spp. infestation.

Resin duct characteristics associated with tree resistance to bark beetles across lodgepole and limber pines

Oecologia ◽  
2013 ◽  
Vol 174 (4) ◽  
pp. 1283-1292 ◽  
Author(s):  
Scott Ferrenberg ◽  
Jeffrey M. Kane ◽  
Jeffry B. Mitton
Keyword(s):  
Bark Beetles ◽  
Resin Duct ◽  
Tree Resistance

scholarly journals Douglas Fir and Ponderosa Pine Seed Dormancy as Regulated by Grassland Seedbed Conditions

2004 ◽  
Vol 57 (6) ◽  
pp. 661 ◽  
Author(s):  
Yuguang Bai ◽  
Don Thompson ◽  
Klaas Broersma
Keyword(s):  
Seed Dormancy ◽  
Ponderosa Pine ◽  
Douglas Fir

scholarly journals Branch junctions and the flow of water through xylem in Douglas-fir and ponderosa pine stems

2003 ◽  
Vol 54 (387) ◽  
pp. 1597-1605 ◽  
Author(s):  
P. J. Schulte
Keyword(s):  
Ponderosa Pine ◽  
Douglas Fir

Assessing the impact of N-fertilization on biochemical composition and biomass of a Douglas-fir canopy—A remote sensing approach

2012 ◽  
Vol 153 ◽  
pp. 124-133 ◽  
Author(s):  
Thomas Hilker ◽  
Lucie Lepine ◽  
Nicholas C. Coops ◽  
Rachhpal S. Jassal ◽  
T. Andrew Black ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Biochemical Composition ◽  
N Fertilization ◽  
Douglas Fir ◽  
The Impact
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