Canopy Opening and Site Preparation Effects on Conifer and Understory Establishment and Growth after an Uneven-Aged Free Selection Regeneration Harvest in the Northern Rocky Mountains, USA

<i>Research Highlights:</i> Forest management is trending toward creating multi-aged forest structures and diverse vegetative compositions. The challenge is successfully designing and implementing treatments that create these diverse forests. Regeneration establishment is the most import...

Full description

Bibliographic Details
Main Authors: Theresa B. Jain, Russell T. Graham, John C. Byrne, Benjamin C. Bright
Format: Article
Language:English
Published: MDPI AG 2020-06-01
Series:Forests
Subjects:
Online Access:https://www.mdpi.com/1999-4907/11/6/622
_version_ 1797566432491339776
author Theresa B. Jain
Russell T. Graham
John C. Byrne
Benjamin C. Bright
author_facet Theresa B. Jain
Russell T. Graham
John C. Byrne
Benjamin C. Bright
author_sort Theresa B. Jain
collection DOAJ
description <i>Research Highlights:</i> Forest management is trending toward creating multi-aged forest structures and diverse vegetative compositions. The challenge is successfully designing and implementing treatments that create these diverse forests. Regeneration establishment is the most important step when applying a silvicultural system because it determines future treatments and optimizes management options. This study provided the minimum canopy openings that favor the establishment of shade-tolerant and shade-intolerant tree species to inform the implementation of uneven-aged management. <i>Background and Objectives</i>: A replicated study was implemented in 2007 in moist mixed-conifer forests to design, apply, and test two silvicultural concepts, canopy opening size and site preparation. Our objective in 2015 was to evaluate tree regeneration establishment and growth and understory vegetation in relation to these two silvicultural concepts. <i>Materials and Methods</i>: Canopy opening sizes as measured by lidar ranged from 15% to 100%; and through the application of prescribed fire, mastication, pile and burn, or no site preparation, different combinations of forest floor substrates were created. We stratified our study area into five canopy opening classes and four site preparation treatments. Using this stratified sampling scheme, we located 65 plots and measured tree species, abundance, 5-year height growth, and vegetative lifeforms. <i>Results:</i> The pile and burn site preparation favored the establishment of all six tree species. The canopy opening size of 55% to 92% favored the regeneration of both shade-tolerant and shade-intolerant species. Grand-fir 5-year height growth was significantly influenced by site preparation and canopy opening, and western white pine 5-year height growth was only influenced by canopy opening. Treatments did not influence vegetative richness. <i>Conclusions:</i> This study provided key treatment parameters in designing the regeneration step for uneven-aged management strategies with the goal of creating vegetative diversity and establishing shade-intolerant tree species in moist mixed-conifer forests.
first_indexed 2024-03-10T19:26:43Z
format Article
id doaj.art-6407bff70e894373867cefb5b2d1422f
institution Directory Open Access Journal
issn 1999-4907
language English
last_indexed 2024-03-10T19:26:43Z
publishDate 2020-06-01
publisher MDPI AG
record_format Article
series Forests
spelling doaj.art-6407bff70e894373867cefb5b2d1422f2023-11-20T02:28:14ZengMDPI AGForests1999-49072020-06-0111662210.3390/f11060622Canopy Opening and Site Preparation Effects on Conifer and Understory Establishment and Growth after an Uneven-Aged Free Selection Regeneration Harvest in the Northern Rocky Mountains, USATheresa B. Jain0Russell T. Graham1John C. Byrne2Benjamin C. Bright3United States Department of Agriculture, Forest Service, Rocky Mountain Research Station, Moscow, ID 83843, USAUnited States Department of Agriculture, Forest Service, Rocky Mountain Research Station, Moscow, ID 83843, USAUnited States Department of Agriculture, Forest Service, Rocky Mountain Research Station, Moscow, ID 83843, USAUnited States Department of Agriculture, Forest Service, Rocky Mountain Research Station, Moscow, ID 83843, USA<i>Research Highlights:</i> Forest management is trending toward creating multi-aged forest structures and diverse vegetative compositions. The challenge is successfully designing and implementing treatments that create these diverse forests. Regeneration establishment is the most important step when applying a silvicultural system because it determines future treatments and optimizes management options. This study provided the minimum canopy openings that favor the establishment of shade-tolerant and shade-intolerant tree species to inform the implementation of uneven-aged management. <i>Background and Objectives</i>: A replicated study was implemented in 2007 in moist mixed-conifer forests to design, apply, and test two silvicultural concepts, canopy opening size and site preparation. Our objective in 2015 was to evaluate tree regeneration establishment and growth and understory vegetation in relation to these two silvicultural concepts. <i>Materials and Methods</i>: Canopy opening sizes as measured by lidar ranged from 15% to 100%; and through the application of prescribed fire, mastication, pile and burn, or no site preparation, different combinations of forest floor substrates were created. We stratified our study area into five canopy opening classes and four site preparation treatments. Using this stratified sampling scheme, we located 65 plots and measured tree species, abundance, 5-year height growth, and vegetative lifeforms. <i>Results:</i> The pile and burn site preparation favored the establishment of all six tree species. The canopy opening size of 55% to 92% favored the regeneration of both shade-tolerant and shade-intolerant species. Grand-fir 5-year height growth was significantly influenced by site preparation and canopy opening, and western white pine 5-year height growth was only influenced by canopy opening. Treatments did not influence vegetative richness. <i>Conclusions:</i> This study provided key treatment parameters in designing the regeneration step for uneven-aged management strategies with the goal of creating vegetative diversity and establishing shade-intolerant tree species in moist mixed-conifer forests.https://www.mdpi.com/1999-4907/11/6/622mixed moist conifershade-intolerant tree specieswestern white pinerestorationvariable density thinningmulti-aged forests
spellingShingle Theresa B. Jain
Russell T. Graham
John C. Byrne
Benjamin C. Bright
Canopy Opening and Site Preparation Effects on Conifer and Understory Establishment and Growth after an Uneven-Aged Free Selection Regeneration Harvest in the Northern Rocky Mountains, USA
Forests
mixed moist conifer
shade-intolerant tree species
western white pine
restoration
variable density thinning
multi-aged forests
title Canopy Opening and Site Preparation Effects on Conifer and Understory Establishment and Growth after an Uneven-Aged Free Selection Regeneration Harvest in the Northern Rocky Mountains, USA
title_full Canopy Opening and Site Preparation Effects on Conifer and Understory Establishment and Growth after an Uneven-Aged Free Selection Regeneration Harvest in the Northern Rocky Mountains, USA
title_fullStr Canopy Opening and Site Preparation Effects on Conifer and Understory Establishment and Growth after an Uneven-Aged Free Selection Regeneration Harvest in the Northern Rocky Mountains, USA
title_full_unstemmed Canopy Opening and Site Preparation Effects on Conifer and Understory Establishment and Growth after an Uneven-Aged Free Selection Regeneration Harvest in the Northern Rocky Mountains, USA
title_short Canopy Opening and Site Preparation Effects on Conifer and Understory Establishment and Growth after an Uneven-Aged Free Selection Regeneration Harvest in the Northern Rocky Mountains, USA
title_sort canopy opening and site preparation effects on conifer and understory establishment and growth after an uneven aged free selection regeneration harvest in the northern rocky mountains usa
topic mixed moist conifer
shade-intolerant tree species
western white pine
restoration
variable density thinning
multi-aged forests
url https://www.mdpi.com/1999-4907/11/6/622
work_keys_str_mv AT theresabjain canopyopeningandsitepreparationeffectsonconiferandunderstoryestablishmentandgrowthafteranunevenagedfreeselectionregenerationharvestinthenorthernrockymountainsusa
AT russelltgraham canopyopeningandsitepreparationeffectsonconiferandunderstoryestablishmentandgrowthafteranunevenagedfreeselectionregenerationharvestinthenorthernrockymountainsusa
AT johncbyrne canopyopeningandsitepreparationeffectsonconiferandunderstoryestablishmentandgrowthafteranunevenagedfreeselectionregenerationharvestinthenorthernrockymountainsusa
AT benjamincbright canopyopeningandsitepreparationeffectsonconiferandunderstoryestablishmentandgrowthafteranunevenagedfreeselectionregenerationharvestinthenorthernrockymountainsusa