Commercial thinning effects on growth, yield and mortality in natural lodgepole pine stands in Alberta

There is an expected decrease in the short to mid-term timber supply of lodgepole pine (Pinus contorta var. latifolia) in Alberta, Canada due to the impacts of past fires and the mountain pine beetle outbreak. Commercial thinning is a potential option for increasing mid-term sawlog timber supply by...

Full description

Saved in:
Bibliographic Details
Main Authors: Sanatan Das Gupta, Bradley D. Pinno, Tim McCready
Format: Article
Language:English
Published: Canadian Institute of Forestry 2020-07-01
Series:The Forestry Chronicle
Subjects:
Online Access:https://pubs.cif-ifc.org/doi/10.5558/tfc2020-016
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849340167857373184
author Sanatan Das Gupta
Bradley D. Pinno
Tim McCready
author_facet Sanatan Das Gupta
Bradley D. Pinno
Tim McCready
author_sort Sanatan Das Gupta
collection DOAJ
description There is an expected decrease in the short to mid-term timber supply of lodgepole pine (Pinus contorta var. latifolia) in Alberta, Canada due to the impacts of past fires and the mountain pine beetle outbreak. Commercial thinning is a potential option for increasing mid-term sawlog timber supply by decreasing the time needed for individual trees to reach merchantable size, through providing access to fiber earlier in the rotation, and from the ability to keep mature stands on the stump longer. In the current study, we evaluated the effects of commercial thinning in stands of different ages. Stands less than 70 years old at thinning were classified as commercial thinning (CT), whereas stands greater than 70 years at thinning were classified as salvage thinning (ST). Tree growth and survival were measured every five years from 1996 to 2016 in both thinned and unthinned stands. Fifteen years post-thinning, stand volume was less in the thinned stands relative to the unthinned controls. However, when volume removed at thinning was considered, volume gain from thinned stands was greater than that from the controls in both thinning treatments. Individual tree DBH and live crown ratio were also greater in thinned stands relative to controls. Thinning favored diameter gain mostly in the medium-sized trees in CT but both small to medium-sized trees in ST. Thinning reduced mortality in all stands relative to the controls and a maximum of 50% reduction in mortality was observed in CT. Overall, the findings suggest that natural lodgepole pine stands may respond to commercial thinning with a net gain in cumulative volume at final harvest.
format Article
id doaj-art-65f5bb28efb0455080c15aa55c5956e8
institution Kabale University
issn 0015-7546
1499-9315
language English
publishDate 2020-07-01
publisher Canadian Institute of Forestry
record_format Article
series The Forestry Chronicle
spelling doaj-art-65f5bb28efb0455080c15aa55c5956e82025-08-20T03:43:58ZengCanadian Institute of ForestryThe Forestry Chronicle0015-75461499-93152020-07-01960211112010.5558/tfc2020-016Commercial thinning effects on growth, yield and mortality in natural lodgepole pine stands in AlbertaSanatan Das Gupta0Bradley D. Pinno1Tim McCready2Department of Renewable Resources, University of Alberta, Edmonton, AB, Canada T6G 2H1Department of Renewable Resources, University of Alberta, Edmonton, AB, Canada T6G 2H1Millar Western Forest Products Ltd., Whitecourt Wood Products Division, Whitecourt, AB, Canada T7S 1N2There is an expected decrease in the short to mid-term timber supply of lodgepole pine (Pinus contorta var. latifolia) in Alberta, Canada due to the impacts of past fires and the mountain pine beetle outbreak. Commercial thinning is a potential option for increasing mid-term sawlog timber supply by decreasing the time needed for individual trees to reach merchantable size, through providing access to fiber earlier in the rotation, and from the ability to keep mature stands on the stump longer. In the current study, we evaluated the effects of commercial thinning in stands of different ages. Stands less than 70 years old at thinning were classified as commercial thinning (CT), whereas stands greater than 70 years at thinning were classified as salvage thinning (ST). Tree growth and survival were measured every five years from 1996 to 2016 in both thinned and unthinned stands. Fifteen years post-thinning, stand volume was less in the thinned stands relative to the unthinned controls. However, when volume removed at thinning was considered, volume gain from thinned stands was greater than that from the controls in both thinning treatments. Individual tree DBH and live crown ratio were also greater in thinned stands relative to controls. Thinning favored diameter gain mostly in the medium-sized trees in CT but both small to medium-sized trees in ST. Thinning reduced mortality in all stands relative to the controls and a maximum of 50% reduction in mortality was observed in CT. Overall, the findings suggest that natural lodgepole pine stands may respond to commercial thinning with a net gain in cumulative volume at final harvest.https://pubs.cif-ifc.org/doi/10.5558/tfc2020-016lodgepole pinecommercial thinningsalvage thinningmortalitystand volumepin lodgepole
spellingShingle Sanatan Das Gupta
Bradley D. Pinno
Tim McCready
Commercial thinning effects on growth, yield and mortality in natural lodgepole pine stands in Alberta
The Forestry Chronicle
lodgepole pine
commercial thinning
salvage thinning
mortality
stand volume
pin lodgepole
title Commercial thinning effects on growth, yield and mortality in natural lodgepole pine stands in Alberta
title_full Commercial thinning effects on growth, yield and mortality in natural lodgepole pine stands in Alberta
title_fullStr Commercial thinning effects on growth, yield and mortality in natural lodgepole pine stands in Alberta
title_full_unstemmed Commercial thinning effects on growth, yield and mortality in natural lodgepole pine stands in Alberta
title_short Commercial thinning effects on growth, yield and mortality in natural lodgepole pine stands in Alberta
title_sort commercial thinning effects on growth yield and mortality in natural lodgepole pine stands in alberta
topic lodgepole pine
commercial thinning
salvage thinning
mortality
stand volume
pin lodgepole
url https://pubs.cif-ifc.org/doi/10.5558/tfc2020-016
work_keys_str_mv AT sanatandasgupta commercialthinningeffectsongrowthyieldandmortalityinnaturallodgepolepinestandsinalberta
AT bradleydpinno commercialthinningeffectsongrowthyieldandmortalityinnaturallodgepolepinestandsinalberta
AT timmccready commercialthinningeffectsongrowthyieldandmortalityinnaturallodgepolepinestandsinalberta