Cultural Practices for Prevention and Mitigation of Mountain Pine Beetle Infestations

Abstract:The mountain pine beetle (Dendroctonus ponderosae Hopkins) (MPB) has infested and killed millions of hectares of lodgepole pine (Pinus contorta var. latifolia Engelm) forests in British Columbia, Canada, over the past decade. It is now spreading out of its native range into the Canadian boreal forest, with unknown social, economic and ecological consequences. This review explores the ramifications of the MPB epidemic with respect to mid-term timber supply, forest growth, structure and composition, vegetation diversity, forest fire, climate change, and ecosystem resilience. Research confirms that, in British Columbia, all of these variables are more significantly impacted when salvage logging is used as management response to the outbreak. We conclude that appropriate management in response to MPB is essential to ensuring ecologically resilient future forests and reliable mid-term timber supplies for affected human communities. We highlight knowledge gaps and avenues for research to advance our understanding in support of sustainable post-disturbance forest management policies in British Columbia and elsewhere.

Section: Introductionmentioning

confidence: 99%

Aftermath of Mountain Pine Beetle Outbreak in British Columbia: Stand Dynamics, Management Response and Ecosystem Resilience

Dhar

Parrott

Hawkins

2016

“…We defined -direct control‖ as short-term tactics designed to address current infestations by manipulating beetle populations, which includes the use of fire, insecticides, semiochemicals, sanitation harvests, or a combination of these treatments. -Indirect control‖ was defined as preventive, and designed to reduce the probability and severity of future infestations within treated areas by manipulating stand, forest and/or landscape conditions by reducing the number of susceptible host trees through thinning, prescribed burning, and/or alterations of age classes and species composition [5]. The focus of indirect control is on the residual structure and composition of forests following treatment, and not on direct impacts to the mountain pine beetle population.…”

mentioning

confidence: 99%

“…Recently, we reviewed tree, stand, and landscape factors associated with mountain pine beetle infestations, and discussed the effectiveness of treatments for preventing and mitigating undesirable levels of tree mortality attributed to mountain pine beetle [5]. We defined -direct control‖ as short-term tactics designed to address current infestations by manipulating beetle populations, which includes the use of fire, insecticides, semiochemicals, sanitation harvests, or a combination of these treatments.…”

mentioning

confidence: 99%

A Comment on “Management for Mountain Pine Beetle Outbreak Suppression: Does Relevant Science Support Current Policy?”

Fettig

Gibson

Munson

et al. 2014

There are two general approaches for reducing the negative impacts of mountain pine beetle, Dendroctonus ponderosae Hopkins, on forests. Direct control involves short-term tactics designed to address current infestations by manipulating mountain pine beetle populations, and includes the use of fire, insecticides, semiochemicals, sanitation harvests, or a combination of these treatments. Indirect control is preventive, and designed to reduce the probability and severity of future infestations within treated areas by manipulating stand, forest and/or landscape conditions by reducing the number of susceptible host trees through thinning, prescribed burning, and/or alterations of age classes and species composition. We emphasize that -outbreak suppression‖ is not the intent or objective of management strategies implemented for mountain pine beetle in the western United States, and that the use of clear, descriptive language is important when assessing the merits of various treatment strategies. OPEN ACCESS

“…However, when mountain pine beetle outbreaks occur, they can extend over years, during which time the beetle can cause extensive tree mortality [2,3]. Mountain pine beetle attacks occur more frequently in stands with higher basal area and stand density index measurements [4]. Further, successfully attacked trees tend to be dominant or co-dominant trees with a larger diameter then adjacent trees [4][5][6].…”

Section: Introductionmentioning

confidence: 99%

“…Mountain pine beetle attacks occur more frequently in stands with higher basal area and stand density index measurements [4]. Further, successfully attacked trees tend to be dominant or co-dominant trees with a larger diameter then adjacent trees [4][5][6].…”

Section: Introductionmentioning

confidence: 99%

Changes in a Primary Resistance Parameter of Lodgepole Pine to Bark Beetle Attack One Year Following Fertilization and Thinning

Cook

Carroll

Kimsey

et al. 2015

Many of the forest soils in the Intermountain West are deficient in several nutrients, including nitrogen (N), potassium (K), sulfur (S) and boron (B) and these deficiencies may impact tree resistance to insect attack. Two potential techniques for manipulating tree resistance are fertilization and thinning. We examined fertilization (both alone and in conjunction with stand thinning). Conifer resistance to bark beetles involves a three-step response, the first stage of which is resin flow. Rapid resin flow can prevent the colonization of bark beetles within a tree. Fertilization with low levels of N resulted in an increase in resin flow while high levels of N did not significantly increase resin flow in treated trees. Thinning did not result in higher concentrations of foliar K or B but did result in higher concentrations of foliar N and S. The highest concentrations of foliar N and S consistently occurred in the trees from thinned treatments, regardless of fertilization. There was a negative correlation between tree growth and resin flow one year following treatments. Increasing available nutrient levels to trees (either through fertilization or stand density management) may result in modified resistance parameters that must be considered when making management decisions.