Course:CONS200/2024WT1/Salvage logging after mountain pine beetle in British Columbia: Overview and implications

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The mountain pine beetle

The mountain pine beetle species (dendroctonus ponderosae) is native to Western Northern America and thrives in warm temperatures. Meaning that their numbers have previously been regulated by British Columbia's (BC) temperature range throughout the seasons[1]. However, after years of relatively warm winters since the 1990s, without their environmental limitations present mountain pine beetle populations have skyrocketed[1]. Mountain pine beetles have been responsible for the decimation of an estimated 18 million hectares of commercial lodgepole pine in British Columbia's Rocky Mountains since the 1990s[2]. Effectively causing a loss of half "the total volume of commercial lodgepole pine in British Columbia"[2]. These beetles' preference for larger, mature pine trees[1] means not only detrimental environmental effects but also devastation to British Columbia's logging industry. In response to decreasing forest resources, British Columbia foresters have adopted an economically oriented logging practice known as salvage logging. In an effort to maximize economic gains, salvage logging essentially clears out trees from previously disturbed areas, leaving little biodiversity behind[3]. Biodiversity is a crucial factor in ecosystem health, contributing to an ecosystem's ability to recover after disturbances like the mountain pine beetle epidemic. Even at full health, ecosystems require time to naturally bounce back after a disturbance. Unfortunately, implementation of salvage logging often occurs too soon after mountain pine beetles have infested an area. Post-salvage logging the forest ecosystem has been hit with two subsequent disturbances, further weakening ecosystem health. Opportunely, knowledge that economic endeavors require a fine balance between economic pay-off and environmental stewardship is growing in popularity amongst commercial industries. Familiar with developing an economy-environment balance, conservationists have discussed potential alterations to the salvage logging practice to allow more space for ecosystems to recover. As it were, the cost-benefit of this practice is largely debated, as from a conservationist perspective no quick economic fix is worth the long term detriment to crucial ecosystems.

What is Salvage Logging

Salvage logging is a forest management practice in which dead or dying trees are harvested for economic value after being damaged by natural disturbances such as pest outbreaks, fires or storms[4]. It is seen increasingly in ecosystems where disturbance events are becoming persistent, such as in British Columbia[5]. Salvage logging is often more intense and extensive than standard logging because it operates on a larger scale and within limited time frames after disturbances--before the timber becomes unsuitable for harvest[5]. It has been practiced in the western world for over a century, dating back to the 1920's in places like the United States and Australia[5].

An example of infected trees (in red) versus healthy trees (in green).

In more recent years, this method has been practiced extensively across British Columbia, particularly due to the widespread devastation caused by large-scale mountain pine beetle outbreaks[6]. As the rapidly-spreading pests bore into the bark of lodgepole pine trees, they disrupt the flow of nutrients and water, turning trees a red-brown colour, and eventually leading to tree death[2]. With over 18 million hectares of forest affected, this scale of destruction has prompted the widespread implementation of salvage logging[6].

Historically, mountain pine beetle populations were regulated by natural cold weather that would significantly reduce their numbers[2]. The effects of climate change that have led to milder winters have allowed the beetles to spread into previously unaffected areas at higher elevations and more northern latitudes[2]. These disturbances can cause sudden and rapid processes that strongly decrease wood quality and therefore timber value[4]. The economic and ecological devastation caused by the mountain pine beetle outbreaks has led to the province deeming the practice necessary to recover as much economic value as possible before the decay renders the trees unsalvageable[6]. This led to the Canadian government increasing allowable annual cuts of up to 80% in areas that were strongly affected by the mountain pine, such as Prince George, Fort St. James, Quesnel, and Nadina Provincial Park[6]. However, the massive scale of these operations has raised concerns about the potential long-term environmental impacts on wildlife and biodiversity in the regions affected[6].

Salvage logging has proven to have many ecological ramifications due to the heavily mechanical processes. The operations pose risks that extend all across forest ecosystems, affecting functions such as soil stability, water flow, nutrient dynamics, carbon sequestration, seed dispersal, vegetation cover, and tree regeneration[4]. Additionally, they negatively impact a forest's ability to further resist invasive species and recover from future disturbances[4]. Studies have also pointed out that causing a secondary disturbance, such as salvage logging, so close in time to a previous one, such as a mountain pine beetle outbreak, may cause further damage to forest health[7][8][9]

A salvage logging operation in progress.

Key factors such as the timing of the logging operations, methods being used, and site characteristics are all variables that significantly influence the impacts of salvage logging on a stand[4]. Starting logging operations too quickly after a disturbance can negatively impact the regeneration of a stand, whereas delayed intervention--postponing logging after a natural disturbance occurs--can allow key ecological functions to stabilize, thereby mitigating disruption[4]. Certain specific methods applied while logging can also have varying impacts. Studies have shown that clear-cutting, which involves removing all the trees in one area, leads to more severe habitat and biodiversity loss compared to selective logging which can retain forest structure and minimize soil disturbance[10][11]. Additionally, site-specific factors such as soil type, slope, and vegetation cover could influence the severity of salvage logging impacts[12]. Areas with fragile soils or steeper slopes are at greater risk of erosion and long term ecological damage[12], which emphasizes the necessity to adapt to local conditions and bear in mind specific considerations when planning post-disturbance salvaging practices.

Environmental Impacts

While salvage logging is thought to slow the spread of mountain pine beetles, it decreases overall ecosystem health because it results in less available deadwood. The availability of deadwood is a vital factor in the succession cycle. Deadwood decomposes and becomes organic matter, which provides nutrients and excess water to new growth in an affected area. Current salvage logging practices, especially regarding the pine beetle outbreak, remove potential organic matter and slow the overall forest regeneration process. A European case study found that the relative abundance of ectomycorrhizal fungi populations dwindled from 67% to just 28% in salvage-logged plots.[13] Additionally, decomposing bacteria populations decreased by up to 80% around these sites.[13] Decomposing bacteria and fungal networks both play critical roles in the availability of soil nutrients. Because these organisms depend on abundant deadwood, logging companies must leave dead trees where they stand to preserve their population abundance. As well as facilitating biological soil regeneration, deadwood inadvertently balances out herbivore populations.[14] Deadwood prevents an overabundance of fir saplings, a vital food source for ecosystem engineers such as deer. Deer populations have skyrocketed exponentially with the advent of the logging industry, and their habits of overgrazing have changed the physical geography of forests around the globe.[14] A high deer population discourages other herbivores from making a habitat in their range, which decreases biodiversity and negatively impacts ecosystem health, so it is important to mitigate their population and discourage a higher deer birth rate.

Because of its importance, conservationists agree that deadwood retention is a sustainable alternative to salvage logging. The Forest Enterprise of the UK encourages logging companies to retain 20-40% of all cut wood on-site, as well as leave at least 10% of all mature stems standing.[15] Incorporating these practices into the Canadian logging industry helps to encourage a healthier ecosystem. Legislation such as the Forest Practices Code of British Columbia Act helps to prioritize deadwood retention.[16] It requires logging companies to research the post-harvest stand structure of commercially forested areas and ensure that these areas retain a diverse stand structure after logging.[16] Companies must choose certain dead trees, or “wildlife trees,” to leave standing to prioritize lasting ecosystem health and quicker regeneration of logged areas.[16] Because each forest requires a different level of stand diversity, they must consult with both research agencies and government organizations. Establishing a line of communication with scientists will help companies to maintain biodiversity and forest health to maximize all of the ecosystem’s possible services.

Selective logging is another possible strategy that prioritizes deadwood retention over economic output. This practice involves seeking out trees of a certain age or species that can be harvested while preserving biodiversity, which would help increase the area’s resilience, mitigating the effects of pine beetles. Because mountain pine beetles primarily make their homes in old-growth pine trees, these trees are heavily targeted in salvage logging practices. However, old-growth pine trees play a vital role in forest ecosystems. Old growth pines, affectionately called Mother Trees, store large amounts of carbon in their root systems. As well as absorbing excess carbon from the atmosphere, their expansive roots connect with the mycorrhizal network and provide neighboring seedlings with the nutrients needed to thrive. Even after they are infested with a disease, mother trees’ roots maintain their connection to the mycorrhizal network.[13] To properly promote ecosystem health it is necessary to consider the underground connections between live wood and dead wood. Because of this, cutting out dead wood in salvage logging practices ultimately proves to be harmful. Selective logging encourages forest workers to preserve a certain amount of old-growth pines, which helps the ecosystem benefit from the vital services they provide.

While selective logging is the most environmentally conscious way to go about mitigating mountain pine beetle outbreaks, it is very difficult to pick which affected trees should be preserved versus cut down. However, new technologies are currently on the rise to aid in this selection process. Satellite technology allows logging companies to map out large swaths of forest, highlighting affected areas and healthy areas.[17] The rising popularity of satellite technology in forestry practices will make selective logging much easier in the coming years.

Mountain pine beetles have had drastic effects on BC forests for years, yet because these beetles are a native species to the area, forests have grown the ability to regenerate from outbreaks. Regeneration is not possible without deadwood and old growth pines, so it is important to leave dead trees standing instead of salvage logging. Because the BC economy is so dependent on logging, companies must turn to selective logging in order to preserve the ecosystem while still making a profit.

Economic Implications

Salvage logging is often viewed as a controversial approach due to the immediate economic benefits in the short term, but potential long term ecological impacts. The rise of globalization has led invasive species such as the mountain pine beetle to become more prevalent, killing trees and disrupting ecosystems[18]. In response, British Columbia’s government has turned to salvage logging as a rapid and effective way to limit the spread of infected trees and minimize the loss of commercial timber[19].

In the short term, salvage logging can be seen as an favorable method for combating invasive species as it generates revenue, stabilizes the timber market, and creates jobs. British Columbia’s forest sector plays a major role in generating revenue for the economy. In 2021 alone, the forest sector contributed $5.9 billion to Gross Domestic Product, and provided $1.9 billion in provincial government revenue[20]. British Columbia’s economy relies heavily on the timber market to bring in revenue. Salvage logging has become a popular forest management method as it helps stabilize the timber market by limiting the spread of infected trees. The forest sector is heavily export-oriented, with forest products export valued at $16.3 billion in 2021, representing 30% of B.C.’s total export value[20]. Salvage logging has helped limit the spread of infected wood, helping stabilize the timber market. Furthermore, industries such as the pulp and paper industry, which accounts for 24% of forest products exported, have created 55,715 direct jobs needed for timber production[20]. The creation of more jobs helps aid GDP, strengthening the economy. It is also important to note that salvage logging also helps access fiber faster, making the production process easier and more economically viable[21]. This is illustrated through the economic theory of the short run average cost curve. In economic terms the short run average cost curve measures the effects of decreasing average costs of inputs while simultaneously increasing average levels of outputs[22]. Salvage logging helps minimize the cost of production when extracting fiber from timber, while also increasing the the amount of fiber taken from each tree, thereby maximizing short term total revenue. Overall, from the standpoint of the government, salvage logging has numerous benefits as it helps stabilize the timber market after a disturbance, benefiting British Columbia's economy.

Ecological impacts of salvage logging

While there is a clear immediate financial benefit of salvage logging, the long term ecological disturbances cannot be ignored. Salvage logging can have severe ecological consequences, as it affects ecosystem services by altering the nutrient cycle, soil erosion, tree regeneration, and resistance to invasive species[3]. The disruption of soil can lead to an increase in natural disasters such as flooding[23]. This effect was seen between year 2021 and 2022 as there was a 5% decline in real GDP in the forestry and logging sector, mainly due to flooding and other natural disturbances[24]. An increase in flooding can also lead to secondary succession which means an ecosystem has been disturbed and now has to rebuild itself[25]. This would put a strain on the economy as the loss of nutrients in the soil would negatively affect the growth of young trees, ultimately reducing timber quality. Additionally, the removal of trees in these areas can limit forest regeneration as these impacts affect an ecosystem's health, also leading to a decline in timber quality and value. This was seen in 2022 as wood product manufacturing sales decreased by 8%, from $16.4 billion in 2021 to $15.1 billion in 2022, this was driven by retreating prices of wood and wood products as timber quality diminished[24]. If more forests start to produce poor quality timber, this will lead to severe impacts on the timber market and overall economy. Furthermore, salvage logging has a negative impact on ecosystem services such as water conditions[19]. Water is an extremely important ecosystem service, as it is used in important economic drivers such as agriculture. If there is limited supply of usable water, this will slowly affect the economy as produce will either not grow or will not be in the right conditions to sell[26]. Overall, in the long term salvage logging hurts the economy as it disrupts ecosystems ultimately affecting timber quality.

While salvage logging benefits the economy in the short term by stabilizing the timber market and creating jobs, its long term ecological impacts can put a strain on these benefits. To ensure the stability of both forest ecosystems and the economy, British Columbia's government should consider using a different type of forest management method, one that benefits both the short and long term outcomes.

Conclusion

Anthropocentrically driven climate change lies at the root of the mountain pine beetle epidemic. If not for the resulting warmer winters, mountain pine beetle populations would maintain self-regulation and species within forest ecosystems would continue to live in harmony. Now, faced with such a large-scale hit to one of British Columbia’s most important industries, anthropocentric ethics remain at the forefront of decision making. Undeniably, studies conducted by Leverkus[3] have proven that the changes made by salvage logging to even seemingly minor ecosystem services (like forest canopy cover), throw off the balance of the entire system and weaken the surrounding environment. Despite extensive research demonstrating a need for better environmental consideration when it comes to forestry practices, British Columbia’s logging industry comes out on top as if the environment is not an economic cost. However, forest science researchers are eager to find a middle ground. For instance, Pons et al.[27] make recommendations like leaving twenty percent of an affected stand unlogged, preserving trees in clumps around the affected stand. While conservation research continues to improve, logging practices should follow promptly. At the end of the day, power lies in the hands of government policies with the authority to instill true change. British Columbia has been well aware of the mountain pine beetle epidemic and its implications for decades. In 2020 Canada’s federal government funded over sixty-four million dollars towards research to control and mitigate the impacts of mountain pine beetles[28], but salvage logging still persists. Furthermore, at the current rate of environmental degradation for rapid economic pay-off, there will soon be limited resources to profit off of. Although salvage logging has been economically beneficial thus far, the subsequent endangerment of the environment effectively endangers the long term economic sustainability of the practice. Moving forward, meetings could be held by the Ministry of Forests to discuss different management methods for forests disturbed by mountain pine beetles. Due to its complicated relationship with biodiversity conservation, salvage logging is better considered a means not an end.

References

Please use the Wikipedia reference style. Provide a citation for every sentence, statement, thought, or bit of data not your own, giving the author, year, AND page. For dictionary references for English-language terms, I strongly recommend you use the Oxford English Dictionary. You can reference foreign-language sources but please also provide translations into English in the reference list.

Note: Before writing your wiki article on the UBC Wiki, it may be helpful to review the tips in Wikipedia: Writing better articles.[29]

  1. ↑ 1.0 1.1 1.2 "Mountain Pine Beetle". Government of British Columbia. January 26, 2024. Retrieved October 30, 2024.
  2. ↑ 2.0 2.1 2.2 2.3 2.4 Natural Resources Canada (October 25, 2013). "Mountain Pine Beetle". Natural Resources Canada.
  3. ↑ 3.0 3.1 3.2 Leverkus, A.B.; et al. (2018). "Salvage logging effects on regulating and supporting ecosystem services — a systematic map". Canadian Journal of Forest Research. 48(9): 983–1000. Explicit use of et al. in: |last= (help)
  4. ↑ 4.0 4.1 4.2 4.3 4.4 4.5 Leverkus AB, Rey Benayas JM, Castro J, Boucher D, Brewer S, Collins BM, et al. Salvage logging effects on regulating and supporting ecosystem services — a systematic map. Canadian Journal of Forest Research. 2018 Sep;48(9):983–1000. https://doi.org/10.1139/cjfr-2018-0114
  5. ↑ 5.0 5.1 5.2 Lindenmayer, D. B., & Noss, R. F. (2006). Salvage Logging, Ecosystem Processes, and Biodiversity Conservation. Conservation Biology, 20(4), 949–958. http://www.jstor.org/stable/3879163
  6. ↑ 6.0 6.1 6.2 6.3 6.4 Snetsinger, J. (2009, November). SR35 Biodiversity Conservation during Salvage Logging in the Central Interior of BC. Forest Practices Board. https://www.bcfpb.ca/wp-content/uploads/2016/04/SR35-Salvage-Logging.pdf
  7. ↑ Karr, James R., Rhodes, Jonathan J., Wayne Minshall, G., Haurer, F. Richard, Beschta, Robert L., Frissell, Christopher A., Perry, David A.. The Effects of Postfire Salvage Logging on Aquatic Ecosystems in the American West, BioScience, Volume 54, Issue 11, November 2004, Pages 1029-1033, https://doi.org/10.1641/0006-3568(2004)054%5B1029:TEOPSL%5D2.0.CO;2
  8. ↑ Van Nieuwstadt M.G.L., Sheil D., and Kartawinata K. 2001. The ecological consequences of logging in the burned forests of East Kalimantan, Indonesia. Conserv. Biol. 15(4): 1183–1186. https://conbio.onlinelibrary.wiley.com/doi/abs/10.1046/j.1523-1739.2001.0150041183.x
  9. ↑ Noss R.F. and Lindenmayer D.B. 2006. The ecological effects of salvage logging after natural disturbance. Conserv. Biol. 20(4): 946–948 https://conbio.onlinelibrary.wiley.com/doi/abs/10.1111/j.1523-1739.2006.00497.x
  10. ↑ Thorn, S., Bässler, C., Brandl, R., Burton, P. J., Cahall, R., Campbell, J. L., Castro, J., Choi, C.-Y., Cobb, T., Donato, D. C., Durska, E., Fontaine, J. B., Gauthier, S., Hebert, C., Hothorn, T., Hutto, R. L., Lee, E.-J., Leverkus, A. B., Lindenmayer, D. B., ... Müller, J. (2017). Impacts of salvage logging on biodiversity: A meta-analysis. Journal of Applied Ecology, 55(1), 279-289.
  11. ↑ Cazzolla Gatti, R., Castaldi, S., Lindsell, J. A., Coomes, D. A., Marchetti, M., & Maesano, M. (2015). The impact of selective logging and clear cutting on forest structure, tree diversity, and above-ground biomass of African tropical forests. Ecological Research, 30(1), 119–132. https://link.springer.com/article/10.1007/s11284-014-1217-3
  12. ↑ 12.0 12.1 Cristina M Rumbaitis, d. R. (2006). Changes in understory composition following catastrophic windthrow and salvage logging in a subalpine forest ecosystem. Canadian Journal of Forest Research, 36(11), 2943-2954. Retrieved from https://www.proquest.com/scholarly-journals/changes-understory-composition-following/docview/230532708/se-2
  13. ↑ 13.0 13.1 13.2 Fink-Hooijer, Florika (12 October, 2022). "Retaining deadwood in disturbed forests reduces changes to soil fungal communities and promotes regeneration". European Commission. Retrieved 4 December, 2024. Check date values in: |access-date=, |date= (help)
  14. ↑ 14.0 14.1 Hagge; Muller; Bassler; Biebl; Brandl; Drexler; Gruppe; Hotes; Hothorn (1 November 2019). "Deadwood retention in forests lowers short-term browsing pressure on silver fir saplings by overabundant deer". ScienceDirect. Retrieved 4 December, 2024. Check date values in: |access-date= (help)
  15. ↑ Stevenson, Alan (2 February, 2002). "Life in the Deadwood" (PDF). Forestry Commission. Retrieved 4 December, 2024. Check date values in: |access-date=, |date= (help)
  16. ↑ 16.0 16.1 16.2 Stone; Parminter; Arsenault; Manning; Densmore; Davis; MacKinnon (2002). "Dead Tree Management in British Columbia" (PDF). USDA. Retrieved 4 Dec, 2024. Check date values in: |access-date= (help)
  17. ↑ "Nurturing Forest Health with Selective Logging". Green Building. October 3, 2022. Retrieved 4 December, 2024. Check date values in: |access-date= (help)
  18. ↑ Bonnamour, Aymeric; Gippet, Jérôme; Bertelsmeier, Cleo (22 August 2021). "Insect and plant invasions follow two waves of globalisation". PubMed Central. Retrieved 05 November 2024. Check date values in: |access-date= (help)
  19. ↑ 19.0 19.1 Leverkus, Alexandro; Gustafsson, Lena; Lindenmayer, David; Castro, Jorge; Benayas, José; Ranius, Thomas; Thorn, Simon (08 June 2020). "Salvage logging effects on regulating ecosystem services and fuel loads". ESA Journal. Retrieved 03 November 2024. Check date values in: |access-date=, |date= (help)
  20. ↑ 20.0 20.1 20.2 "2021 B.C. Forest Sector - Statistics Summary" (PDF). British Columbia Forest Sector. 03 January 2022. Retrieved 08 November 2024. Check date values in: |access-date=, |date= (help)
  21. ↑ "Wildfire-damaged wood recovery underway in B.C." British Columbia Government. 10 April 2024. Retrieved 09 November 2024. Check date values in: |access-date= (help)
  22. ↑ Maclachlan, Fiona (January 2010). "Long- run and short- run cost curves". ResearchGate. Retrieved 05 November 2024. Check date values in: |access-date= (help)
  23. ↑ Leverkus, Alexandro; Buma, Brian; Wagenbrenner, Joseph; Burton, Philip; Lingua, Emanuele; Marzano, Raffaella; Thorn, Simon (01 February 2021). "Tamm review: Does salvage logging mitigate subsequent forest disturbances?". Science Direct. Retrieved 05 November 2024. Check date values in: |access-date=, |date= (help)
  24. ↑ 24.0 24.1 "2022 Economic State of British Columbia's Forest Sector" (PDF). British Columbia Forest Sector. 03 January 2023. Retrieved 09 November 2024. line feed character in |title= at position 42 (help); Check date values in: |access-date=, |date= (help)
  25. ↑ Perez-Hernandez, Javier; Gavilan, Rosario (16 May 2021). "Impacts of Land-Use Changes on Vegetation and Ecosystem Functioning: Old-Field Secondary Succession". MDPI. Retrieved 08 November 2024. Check date values in: |access-date= (help)
  26. ↑ Farley, Joshua (2012 April 2012). "Ecosystem services: The economics debate". Science Direct. Retrieved 06 November 2024. Check date values in: |access-date=, |date= (help)
  27. ↑ 1. Pons 2. Rost 3. Tobella 4. Puig-Gironès 5. Bas 6. Franch 7. Mauri, 1. P 2. J 3. C 4. R 5. J 6. M 7. E (2020). "Towards better practices of salvage logging for reducing the ecosystem impacts in Mediterranean burned forests". iForest - Biogeosciences and Forestry. 13. SISEF. pp. 360–368. doi:https://doi.org/10.3832/ifor3380-013 Check |doi= value (help).
  28. ↑ Natural Resources Canada (October 8, 2020). "Protecting Canada's Forests From the Mountain Pine Beetle". Government of Canada.
  29. ↑ En.wikipedia.org. (2018). Writing better articles. [online] Available at: https://en.wikipedia.org/wiki/Wikipedia:Writing_better_articles [Accessed 18 Jan. 2018].
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