Agriculture and forestry

Project type: Research

Description: Agricultural land expansion is of interest to the Yukon; however, much of the land in the Yukon with farming potential is currently forested. Conventional methods of land clearing involve clearing and piling above ground forest and large roots with bladed machines, burning the organic materials, and spreading the ash. This practice removes organics from the system, releases large amounts of greenhouse gases in a short period, and the ash is of little soil development benefit to future agricultural endeavors. In the interest of retaining and using the organics as a potentially beneficial soil amendment instead of burning it as waste, Government of Yukon Agriculture Branch proposed to experiment with different clearing methods involving incorporation of the forest organics into the soil. Concerns over the decomposing wood chips in soil ‘stealing’ nitrogen (immobilization) from other growing plants was addressed in a literature review in 2017. The review concluded that nitrogen immobilization, while expected, may be a short-lived phenomenon as the more readily decomposable materials will do so in the first year, and the more resilient organics will decompose so slowly in our cold northern soils that they will have a negligible effect on the available soil nitrogen.

Funding was obtained through Agriculture and Agrifood Canada’s Canadian Agricultural Partnerships fund to implement a field trial exploring two different methods of incorporating the cleared forest organic materials into newly established agricultural plots. The first method was to use a forestry mulcher and subsoiler to shred and churn the organics in place into the top layers of the soil. The second method was to collect and shred the woody organics into a pile, then top-spread approximately one-third of the shredded material immediately after seeding for the following three years of the trial. A third treatment of conventional clear and burn was used as a comparison. The study took place in the Murray Agricultural Subdivision of the Ibex Valley, Yukon. Initial clearing and mulching was completed in 2020. Four, 30mx120m plots of each of the three treatments were randomly assigned in a block design and planted with oats with a standard fertilizer blend in both 2021 and 2022. Soil from each plot was sampled at key times throughout the trial and analyzed for nutrients, general chemistry, texture, and microbiology. In-situ temperature and moisture monitors were installed in each plot, and yield sampling of each plot was done in the fall of each year. Equipment operators recorded their fuel use, and greenhouse gas emissions and development costs were calculated and recorded for each treatment.

Primary contact: Jonathan Lucas, Yukon Energy, Mines and Resources,  jonathan.lucas@yukon.ca  Principle investigator: Rachel Pugh, Yukon University

Project partners : Yukon Energy, Mines and Resources – Agriculture Branch; Yukon University – Yukon Research Centre; Agriculture and Agri-food Canada, Harrow Research and Development Centre

Project funding: Agriculture and Agri-food Canada Regional Collaborative Partnerships Program; Government of Northwest Territories; Government of Yukon

More information:

•  Final report 
•  Appendix C - microbiology 

Project type:  Research

Project description: To gain a better understanding of the growth and health of reforestation seed sources from British Columbia and the western United States when planted across a range of climates and latitudes. Nine different species were planted at the Whitehorse site in June 2011: Douglas fir, western hemlock, western larch, lodgepole pine, white pine, spruce, trembling aspen, ponderosa pine, and sub-alpine fir. Over time, the growth and health of the seedlings will be monitored and related to the climate of the plantations, enabling researchers to identify the seed sources most likely to be best adapted to current and future climates.​

Principle investigator: Greg O'Neill, BC Ministry of Forests, Lands and Natural Resource Operations

Project partners:  Forest Management Branch, Department of Energy Mines and Resources, Government of Yukon 

Contact:  Robin Sharples  Map notes: The map below shows the locations where seed was sourced that are being studied in the assisted migration adaptation trial along with the location of the test sites.  

Photo notes: The photo opposite shows seedlings sourced and planted at various reforestation sites in the AMAT trial. Photo credit: Government of British Columbia

Project type: Research

Description: Working with the Fuel Abatement Working Group, the aim of the project is to create a landscape level fire break to the village of Haines Junction and determine the effectiveness of converting coniferous forest stands to deciduous stands with a post-harvest planting program. Trembling Aspen (Populus tremuloides) seedlings were planted in June 2015 in recently harvested coniferous cut blocks. Seedlings were planted at different densities of 800, 1600, and 2000 Stems Per Hectare (SPH) in one cut block to determine the optimal local planting density for Aspen. The survival and growth of 140 planted seedlings will be followed through time with measurements being collected approximately every five years. 

Contact:  Forestry@yukon.ca  

Photo notes: The photo opposite shows planted Aspen seedlings marked with flags in the density planting trial of the Block Zero stand conversion near the Village of Haines Junction. 

Map notes: The map below shows the location of the Block Zero stand conversion planting trial near the Village of Haines Junction.

Project type: Research 

Description: This study is aimed at identifying forest harvesting practices that would minimize deleterious impacts on terrestrial forage lichens in the winter range of the Carcross caribou herd. ​Very little formal research has been conducted in the Yukon on the relationship between canopy closure and lichen abundance in response to variable retention forest harvesting systems. The aim of this study is to provide an opportunity to conduct research to explore the relationships and provide guidance on when, where, and how to prescribe variable retention harvesting treatments in known southern lakes caribou lichen habitat. The results may assist with the development of forestry best management practices and mitigations during planning and project assessments. Plots were sampled prior to timber harvesting, post timber harvesting (2016) and scheduled to be sampled in 2021 and 2022, 2030, and 2040. 

Principle investigator: Robin Sharples, Forest Management Branch, Department of Energy, Mines and Resources  

Project partners:  Department of Environment, Government of Yukon 

Contact:  Forestry@yukon.ca 

Map notes: The map opposite shows the location of the variable retention harvesting treatment blocks.   

More information:  Lewes Marsh Caribou Lichen - Research and Monitoring Phase 2 Report on 2016 Post-Harvest Assessments  

 Lewes Marsh Caribou Lichen - Research and Monitoring Phase 2 Report on 2017 Post-Harvest Shrub Assessments 

 Lewes Marsh Caribou Lichen - Research and Monitoring - Report on 2022/23 Post-Harvest Assessments 

Project type: Research

Project description: The objective of this project is to identify forest vulnerabilities and community adaptation strategies in Teslin, Yukon through a community directed process. This process is intended to support informed community decision-making in order to facilitate effective adaptive strategies. In Phases 1 and 2 of the project, the goal was to work closely with project partners and community knowledge holders to confirm, better understand and build awareness about how changes in the forests and climate in the Teslin region are increasing the risk of catastrophic forest fire. Phases 3 and 4 of the project (fiscal 2014/15 and 2015/16) are intended to facilitate community adaptation planning and decision-making on how these concerns can be addressed. 

Principle investigator: Scott Green, Department of Ecosystems Science and Management, University of Northern British Columbia 

Project partners:  Forest Management Branch, Government of Yukon; Teslin Tlingit Council; Teslin Renewable Resource Council.

Contact:  Robin Sharples  

Map notes: The map opposite shows the Teslin Tlingit Traditional Territory, the study area for this project.  Click here to open the map in a new window.  

 More information 

Project type: Monitoring 

Description:  The objectives of Yukon's Forest Health Monitoring Program are to: 1) provide a Yukon-wide overview of forest health issues; 2) focus monitoring activities on high-risk forest health concerns across forested landscapes that are considered the most value to Yukon residents; and 3) monitor and assess forest health concerns and to determine and evaluate forest management responses. Yukon is divided into five forest health zones. Each year since 2009, aerial surveys have been completed on one of the five zones. Monitoring focuses on the 10 forest health agents of greatest concern. 

Contact:   Forestry@yukon.ca 

Map notes: The map opposite shows mapping completed under the forest health monitoring program. Forest health issues are mapped by the causal agent, as shown in the legend. Click on a polygon to view the survey year that the disturbance was observed.  Click here to open the map in a new window.  

 Forest Health Reports 

Project type: Research 

Description: Climate change is having an impact on northern boreal forests in part because of increased temperatures. Beetle outbreaks are becoming more common and the biggest health concern for lodgepole pine forests in western Canada is the mountain pine beetle (MPB). Currently the MPB is not present in Yukon, however it has been moving northward and is near the Yukon/BC border. This research will provide a realistic assessment of the risk that the beetle has on Yukon pine forests before it arrives in Yukon. The objectives for this project are to: 

• develop a climatic model for the mountain pine beetle relevant to northern pine forests;
• create an index for northern lodgepole pine forests that have not co-evolved with the beetle;
• combine the climate models with future climate projections to predict the potential for the beetle to establish, spread and impact the lodgepole pine forests in southern Yukon; and
• develop decision support tools that will provide forest managers with tools to manage the beetle in Yukon.

Map notes: The Government of Yukon conducts annual aerial surveys in the border monitoring zone (shown in the map opposite) that stretches from the Rancheria River in the west to near the Northwest Territories border to monitor / detect any northward expansion of the Mountain Pine Beetle into Yukon.  The map opposite also provides information on observations made during recent surveys.  Click here to open the map in a new window.  

Principle investigator: University of British Columbia

Project partners: Forest Management Branch, Government of Yukon

Contact:  Robin Sharples  

 More information 

Project type: Monitoring 

Description: The Forest Resources Permanent Sample Plot (PSP) program was initiated in 1988 to collect data on the growth and development of forests in Yukon. Approximately 300 PSPs have been established in locations throughout southern Yukon. The purpose of theseplots is to provide growth and mortality information on the Yukon's forests. The long range goal is to be able to track the growth, development, and yield of forest stands from establishment to reestablishment (fire to fire or harvest to harvest).   Contact:   Forestry@yukon.ca 

Map notes: The map opposite shows the location of all permanent sample plots in Yukon. Click on a plot to view its exact geographic coordinates.  Click here to open the map in a new window.  

 More information 

Project type: Research 

Project description: To gain a better understanding of how white spruce has responded to the spruce bark beetle in southwestern Yukon. In 2000 and 2002, 27 forest assessment plots were established within the area infested by spruce bark beetle, Dendroctonus rufipennis in southwest Yukon. The study objective was to document long-term changes in white spruce (Picea glauca) mortality, stand structure, regeneration, surface vegetation, and surface woody fuel load. A partial re-measurement was conducted in 2010 and 2016. Plots are scheduled to be re-measured in 2024.

Principle investigator: Elizabeth Campbell, Canadian Forest Service, Pacific Forestry Centre 

Project partners: Forest Management Branch, Department of Energy Mines and Resources, Government of Yukon

Contact:  Forestry@yukon.ca 

Report:  Resilience of southern Yukon boreal forests to spruce beetle outbreaks  

Map notes: The map below shows the location of the plots that the Canadian Forest Service (CFS) has installed in southwest Yukon to monitor the response of forests to the spruce infestation. 

Project type: Monitoring

Description: Permanent sample plots (PSPs) were established in southern Yukon in 1988 and in the Dawson area in 2018-19 to provide long-term information to forest managers on the growth dynamics and species composition of forests. PSPs are the primary method used to monitor forest dynamics and changes in species composition, growth and mortality. 

The objective of this project is to provide information on the growth dynamics and changes in species composition of Yukon forests. The collected information will be compiled to create Yukon specific forest inventory and growth models. Utilizing permanent sample plots and building upon the existing tree growth and yield monitoring program in Yukon the project will help identify areas in the northern-most extent of the Boreal Cordillera that may be affected by climate change as well as other factors affecting northern forests.   

The PSP data is being used to support climate change modelling, carbon modeling and other landscape level research and assessments. Information including inventory, growth and yield dynamics and possible species migration has been shared with universities and governmental departments and will assist forest management planning activities throughout Yukon. 

Principle investigator: Robert Legare, Department of Energy Mines and Resources, Government of Yukon 

Project partners: Tr’ondëk Hwëch’in, Canadian Forest Service

Contact:   Forestry@yukon.ca 

Map notes: The map opposite shows the location of all permanent sample plots in the Dawson area.