Forest thinning and subsequent bark beetle-caused mortality in Northeastern California

Egan, Joel M.; Jacobi, William R.; Negrón, José F.; Smith, Sheri L.; Cluck, Daniel R.

doi:10.1016/j.foreco.2010.08.030

Cited by 28 publications

(37 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Previous thinning studies have used total trees or basal area killed [24][25][26], proportion of trees [27,28], or both [29,30] when assessing effectiveness of silvicultural treatments. While we tested proportion of total trees attacked and the total number of trees attacked, the former may not be an appropriate measure for assessing S. noctilio response to stand thinnings.…”

Section: Discussionmentioning

confidence: 99%

The Effects of Silvicultural Treatment on Sirex noctilio Attacks and Tree Health in Northeastern United States

Dodds

Cooke

Hanavan

2014

Forests

View full text Add to dashboard Cite

Abstract:The invasive woodwasp Sirex noctilio (Hymenoptera: Siricidae) is established in east-central North America. A replicated case study testing the effectiveness of silvicultural treatments for reducing the number of S. noctilio attacked trees in a stand was conducted in New York, USA. Silvicultural treatments reduced S. noctilio attacked trees by approximately 75% over the course of the study. There was no tree growth response to silvicultural treatments in the four years after thinning, but targeted removal of weakened trees removed potential S. noctilio habitat from treated stands. Two spectral vegetation indices were used to determine tree health in each treatment and potentially provide guidance for detection efforts. Silvicultural treatment significantly influenced the Red Edge Inflection Point, a strong indicator of chlorophyll content, and the Moisture Stress Index, a reflectance measurement sensitive to changes in foliar leaf water content, with the greatest differences occurring between control and treated blocks. Vegetation indices showed promise as a tool for aiding in stand prioritization for S. noctilio surveys or management activities.

show abstract

Section: Discussionmentioning

confidence: 99%

The Effects of Silvicultural Treatment on Sirex noctilio Attacks and Tree Health in Northeastern United States

Dodds

Cooke

Hanavan

2014

Forests

View full text Add to dashboard Cite

show abstract

“…Several studies have reported striking differences in mortality to trees caused by beetles in thinned vs. un-thinned forests (reviewed in [120,121]). In contrast, only a small number of studies have reported failures.…”

Section: Efficacy Of Indirect Controlsmentioning

confidence: 99%

“…When humans thin, they select for particular size classes, often favoring the retention of larger, older trees, selecting toward one desired tree species, and often 'thinning from below' which removes advanced regeneration (small trees) [123,136]. Thinning prescriptions also typically call for relatively even spacing between residual trees [92,107,121]. Mountain pine beetle, on the other hand, often selects the largest trees during outbreaks (with exceptions; [121,123,131]) which can lower the mean diameter of the stand [128].…”

Section: What Are the Goals?mentioning

confidence: 99%

“…Thinning prescriptions also typically call for relatively even spacing between residual trees [92,107,121]. Mountain pine beetle, on the other hand, often selects the largest trees during outbreaks (with exceptions; [121,123,131]) which can lower the mean diameter of the stand [128]. However, beetles often leave sufficient numbers of large diameter trees to maintain a dominant overstory of pine.…”

Section: What Are the Goals?mentioning

confidence: 99%

“…However, beetles often leave sufficient numbers of large diameter trees to maintain a dominant overstory of pine. Beetles also leave substantial amounts of advanced regeneration to replace the mature trees that arekilled [121,129]. Spacing among trees after an outbreak is uneven, resulting in a clumpy network of living trees [129].…”

Section: What Are the Goals?mentioning

confidence: 99%

See 2 more Smart Citations

Management for Mountain Pine Beetle Outbreak Suppression: Does Relevant Science Support Current Policy?

Six

Biber

Long

2014

Forests

View full text Add to dashboard Cite

While the use of timber harvests is generally accepted as an effective approach to controlling bark beetles during outbreaks, in reality there has been a dearth of monitoring to assess outcomes, and failures are often not reported. Additionally, few studies have focused on how these treatments affect forest structure and function over the long term, or our forests' ability to adapt to climate change. Despite this, there is a widespread belief in the policy arena that timber harvesting is an effective and necessary tool to address beetle infestations. That belief has led to numerous proposals for, and enactment of, significant changes in federal environmental laws to encourage more timber harvests for beetle control. In this review, we use mountain pine beetle as an exemplar to critically evaluate the state of science behind the use of timber harvest treatments for bark beetle suppression during outbreaks. It is our hope that this review will stimulate research to fill important gaps and to help guide the development of policy and management firmly based in science, and thus, more likely to aid in forest conservation, reduce financial waste, and bolster public trust in public agency decision-making and practice.

show abstract

Forest structure and climate mediate drought‐induced tree mortality in forests of the Sierra Nevada,USA

Restaino

Young

Estes

et al. 2019

Ecological Applications

102

View full text Add to dashboard Cite

Extreme drought stress and associated bark beetle population growth contributed to an extensive tree mortality event in California, USA, resulting in more than 129 million trees dying between 2012 and 2016. Although drought is an important driver of this mortality event, past and ongoing fire suppression and the consequent densification of forests may have contributed. In some areas, land management agencies have worked to reduce stand density through mechanical treatments and prescribed fire to restore forests to less dense, more open conditions that are presumably more resilient to disturbance and changing climate. Here, we evaluate if stand structural conditions associated with treated (e.g., thinned and prescribed burned) forests in the Sierra Nevada of California conferred more resistance to the bark beetle epidemic and drought event of 2012–2016. We found that, compared to untreated units, treated units had lower stand densities, larger average tree diameters, and greater dominance of pines (Pinus), the historically dominant trees. For all tree species studied, mortality was substantially greater in climatically drier areas (i.e., lower elevations and latitudes). Both pine species studied (ponderosa pine [Pinus ponderosa] and sugar pine [Pinus lambertiana]) had greater mortality in areas where their diameters were larger, suggesting a size preference for their insect mortality agents. For ponderosa pine, the tree species experiencing greatest mortality, individual‐tree mortality probability (for a given tree diameter) was significantly lower in treated stands. Ponderosa pine mortality was also positively related to density of medium‐ to large‐sized conspecific trees, especially in areas with lower precipitation, suggesting that abundance of nearby host trees for insect mortality agents was an important determinant of pine mortality. Mortality of incense cedar (Calocedrus decurrens) and white fir (Abies concolor) was positively associated with basal area, suggesting sensitivity to competition during drought, but overall mortality was lower, likely because the most prevalent and effective mortality agents (the bark beetles Dendroctonus brevicomis and D. ponderosae) are associated specifically with pine species within our study region. Our findings suggest that forest thinning treatments are effective in reducing drought‐related tree mortality in forests, and they underscore the important interaction between water and forest density in mediating bark beetle‐caused mortality.

show abstract

Forest thinning and subsequent bark beetle-caused mortality in Northeastern California

Cited by 28 publications

References 39 publications

The Effects of Silvicultural Treatment on Sirex noctilio Attacks and Tree Health in Northeastern United States

The Effects of Silvicultural Treatment on Sirex noctilio Attacks and Tree Health in Northeastern United States

Management for Mountain Pine Beetle Outbreak Suppression: Does Relevant Science Support Current Policy?

Forest structure and climate mediate drought‐induced tree mortality in forests of the Sierra Nevada,USA

Contact Info

Product

Resources

About