Infestation Phases and Impacts of <i>Dryocoetes confusus</i> in Subalpine Fir Forests of Southern British Columbia
Subalpine fir mortality and stand decline are increasingly evident in British Columbia (B.C.). This long-term study confirmed <i>Dryocoetes confusus</i> to be the major disturbance agent in high-elevation subalpine forests, killing over two-thirds of subalpine fir in eleven one-hectare s...
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-02-01
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| Series: | Forests |
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| Online Access: | https://www.mdpi.com/1999-4907/14/2/363 |
| _version_ | 1797620972075876352 |
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| author | Lorraine E. Maclauchlan Arthur J. Stock Julie E. Brooks |
| author_facet | Lorraine E. Maclauchlan Arthur J. Stock Julie E. Brooks |
| author_sort | Lorraine E. Maclauchlan |
| collection | DOAJ |
| description | Subalpine fir mortality and stand decline are increasingly evident in British Columbia (B.C.). This long-term study confirmed <i>Dryocoetes confusus</i> to be the major disturbance agent in high-elevation subalpine forests, killing over two-thirds of subalpine fir in eleven one-hectare study plots. <i>D. confusus</i> infestations in mature stands can be described as early-, mid-, or late-phase. The transition from the early- through late-phase is characterized by a lowered stem density as high levels of <i>D. confusus</i> attack and remove the largest trees, while other mortality factors kill smaller trees. Initially, live subalpine fir density and <i>D. confusus</i> activity varied among plots. By a final assessment, very little difference was observed in live stems per hectare. Mortality from all factors ranged from 0.5% to 5% annually, reaching as high as 80% in-stand mortality with >6 times more dead than live volume. When subalpine fir density was reduced to <400 sph, the <i>D. confusus</i> attack rate declined. Cumulative mortality increased the average gap size in plots from 11 m<sup>2</sup> to 18 m<sup>2</sup>. Our study also showed that <i>D. confusus</i> might be able to switch to a univoltine life cycle, taking advantage of warmer and longer growing seasons that, in part, could explain the rapid increase in mortality in stands. |
| first_indexed | 2024-03-11T08:49:07Z |
| format | Article |
| id | doaj.art-adcf04be1a66421787b30e2b847b0702 |
| institution | Directory Open Access Journal |
| issn | 1999-4907 |
| language | English |
| last_indexed | 2024-03-11T08:49:07Z |
| publishDate | 2023-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Forests |
| spelling | doaj.art-adcf04be1a66421787b30e2b847b07022023-11-16T20:34:55ZengMDPI AGForests1999-49072023-02-0114236310.3390/f14020363Infestation Phases and Impacts of <i>Dryocoetes confusus</i> in Subalpine Fir Forests of Southern British ColumbiaLorraine E. Maclauchlan0Arthur J. Stock1Julie E. Brooks2B.C. Ministry of Forests, 441 Columbia Street, Kamloops, BC V2C 2T3, CanadaIndependent Researcher, 515 Fourth Street, Nelson, BC V1L 2S4, CanadaIndependent Researcher, 466 Central Avenue, Gibsons, BC V0N 1V1, CanadaSubalpine fir mortality and stand decline are increasingly evident in British Columbia (B.C.). This long-term study confirmed <i>Dryocoetes confusus</i> to be the major disturbance agent in high-elevation subalpine forests, killing over two-thirds of subalpine fir in eleven one-hectare study plots. <i>D. confusus</i> infestations in mature stands can be described as early-, mid-, or late-phase. The transition from the early- through late-phase is characterized by a lowered stem density as high levels of <i>D. confusus</i> attack and remove the largest trees, while other mortality factors kill smaller trees. Initially, live subalpine fir density and <i>D. confusus</i> activity varied among plots. By a final assessment, very little difference was observed in live stems per hectare. Mortality from all factors ranged from 0.5% to 5% annually, reaching as high as 80% in-stand mortality with >6 times more dead than live volume. When subalpine fir density was reduced to <400 sph, the <i>D. confusus</i> attack rate declined. Cumulative mortality increased the average gap size in plots from 11 m<sup>2</sup> to 18 m<sup>2</sup>. Our study also showed that <i>D. confusus</i> might be able to switch to a univoltine life cycle, taking advantage of warmer and longer growing seasons that, in part, could explain the rapid increase in mortality in stands.https://www.mdpi.com/1999-4907/14/2/363<i>Dryocoetes confusus</i>outbreak phasessubalpine fir declinestand losses |
| spellingShingle | Lorraine E. Maclauchlan Arthur J. Stock Julie E. Brooks Infestation Phases and Impacts of <i>Dryocoetes confusus</i> in Subalpine Fir Forests of Southern British Columbia Forests <i>Dryocoetes confusus</i> outbreak phases subalpine fir decline stand losses |
| title | Infestation Phases and Impacts of <i>Dryocoetes confusus</i> in Subalpine Fir Forests of Southern British Columbia |
| title_full | Infestation Phases and Impacts of <i>Dryocoetes confusus</i> in Subalpine Fir Forests of Southern British Columbia |
| title_fullStr | Infestation Phases and Impacts of <i>Dryocoetes confusus</i> in Subalpine Fir Forests of Southern British Columbia |
| title_full_unstemmed | Infestation Phases and Impacts of <i>Dryocoetes confusus</i> in Subalpine Fir Forests of Southern British Columbia |
| title_short | Infestation Phases and Impacts of <i>Dryocoetes confusus</i> in Subalpine Fir Forests of Southern British Columbia |
| title_sort | infestation phases and impacts of i dryocoetes confusus i in subalpine fir forests of southern british columbia |
| topic | <i>Dryocoetes confusus</i> outbreak phases subalpine fir decline stand losses |
| url | https://www.mdpi.com/1999-4907/14/2/363 |
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