Biomass Reforestation of Boreal Forests a Review of Project Performance and Data Collection

ACEP Technical Report Biomass Reforestation of Boreal Forests A review of project performance and data collection

Chris Pike May 30, 2019

EETF Overview New technology passes through a variety of phases as it proceeds from development and testing in the laboratory to commercialization in the real world. Emergence is a critical middle phase in the development process of energy technology, linking research and development to the commercialization of energy solutions. Although the Arctic possesses bountiful energy resources, the Arctic also faces unique conditions in terms of extreme climate and environmental conditions, low population densities, high energy costs, challenging logistics, and the isolated nature of community electrical generation and transmission systems. These conditions make the Arctic an ideal and rugged test bed for energy technology. Emerging energy technology provides a unique opportunity to meet Arctic energy needs, develop energy resources, and create global expertise.

Building on the success of the Emerging Energy Technology Grant, funded by the Denali Commission in 2009, the Alaska State Legislature created the Emerging Energy Technology Fund (EETF) in 2010 to promote the expansion of energy sources available to Alaskans. These grants, managed by the Alaska Energy Authority, are for demonstration projects of technologies that have a reasonable expectation of becoming commercially viable within five years. Projects can  test emerging energy technologies or methods of conserving energy;  improve an existing technology; or  deploy an existing technology that has not previously been demonstrated in the state.

The funded projects for Round 1 of the EETF include the following: Alaska Division of Forestry, Biomass Reforestation of Boreal Forests Altaeros Energies, Inc., High Altitude Airborne Wind Turbine Alaska Applied Sciences, Inc., Solid State Ammonia Synthesis Pilot Plant Demonstration System Arctic Sun, LLC, Arctic Thermal Shutter & Door Development Boschma Research, Inc., Cyclo-Hydrokinetic Turbine Energy Production Cold Climate Housing Research Center, Cold Climate Ground Source Heat Pump Demonstration Genesis Machining ad Fabrication, Ultra-Efficient Generators and Diesel-Electric Propulsion Hatch, Application of Flywheels for the Integration of Wind-Diesel Hybrid Systems Intelligent Energy Systems, Small Community Self Regulating Grid Intelligent Energy Systems, Wind Diesel Battery Hybrid System Marsh Creek LLC, High Efficiency Diesel Electric Generator for Energy Projects in Alaska Northwest Arctic Borough and Kotzebue Electric, Testing of a 25 kW Wind Turbine Oceana Energy Company, In-Stream Hydrokinetic Device Evaluation Ocean Renewable Power Corporation, RivGen™ Power System Commercialization Project University of Alaska Fairbanks, Safe and Efficient Exhaust Thimble University of Alaska Fairbanks, Enhanced Condensation for Organic Rankine Cycle

Award recipients for EETF grants are selected through a competitive application process. Project selection for the EETF program uses a two-stage application process and has a volunteer advisory committee appointed by the governor.

Project Introduction Deriving heat energy from the combustion of biomass has been practiced since time immemorial. Burning driftwood and seal oil for heat and light allowed Alaska Natives to survive long cold northern winters. In territorial Alaska, wood was harvested and burned to provide transportation on steamships, electricity in Fairbanks, and heat for homes.

The volatile price of fossil fuels and the desire to utilize local and low carbon energy sources is inspiring the search for new energy sources. In Alaska, the high cost of fossil fuels in remote areas further contributes to this effort. The Alaska Energy Authority selected the Alaska Division of Forestry to receive funding from Round 1 of the Emerging Energy Technology Fund to study new ways to grow poplar trees, which can serve as a fast growing source of biomass. The overall goal was to expand the options for biomass generation and demonstrate inexpensive reforestation methods following the harvest of woody biomass in many areas of the state.

The following organizations were involved in the project:

Alaska Department of Forestry

Jeff Graham, Ph.D. is the Forest Stewardship Coordinator with the Alaska Division of Forestry. Graham has over twenty years of experience with forestry in Alaska and has authored scientific and technical publications regarding forest management and regeneration.

University of Alaska Cooperative Extension

Valerie Barber, Ph.D. is an assistant research professor and forestry/climate change specialist at the University of Alaska Fairbanks Cooperative Extension and School of Agriculture and Natural Resources Palmer Center for Sustainable Living. Barber has twenty years of experience studying climate change and growth response of trees in Alaska forests and has authored or coauthored peer reviewed journals and technical papers. Her current research involves agroforestry in Alaska.

University of Alaska Fairbanks School of Natural Resources and Agricultural Sciences Agricultural and Forestry Experiment Station

The University of Alaska Fairbanks (UAF) School of Natural Resources permitted the use of the Delta Junction Field Research Site and the Matanuska Experimental Farm for planting and poplar stooling-bed experiments.

United States Department of Forestry

The U.S. Department of Forestry Provided $45k in matching funds for this project.

Alaska Center for Energy and Power The Alaska Center for Energy and Power (ACEP), an applied energy research program based at UAF, provided technical support for data collection. In addition, ACEP provided independent project and performance analysis and reporting. This report is the final product of that effort.

Technology Overview Biomass is likely the oldest source of energy in Alaska, used by Native Alaskans and early settlers to provide light and heat. Wood was probably the most common source of biomass, but depending on the region, animal-derived fats and oils were also harvested and utilized for cooking, lighting, and heating. Wood stoves were once the primary source of heat in most buildings around the state, and they are still very common in many regions.

In the late 1800s and early 1900s, steam powered stern wheeled river boats traveled up and down Alaska’s rivers and needed a constant supply of wood for fuel. In the interior of the state, the N.C. Company wood-fired power plant provided electricity to the young city of Fairbanks and required a steady supply of timber1. During this time, the hills surrounding Fairbanks were largely deforested.

As renewed attention is focused on reducing costs, lowering carbon footprints, and using sustainable and locally available sources of energy, biomass is being reexamined as a viable feed stock. New varieties of biomass as well as innovative ways to replace already harvested biomass are being studied by researchers.

The Alaska Department of Forestry (DOF) was awarded an Emerging Energy Technology Fund award by the Alaska Energy Authority to study new and untested reforestation methods of planting several varieties of poplars. According to the DOF grant application, the Alaska Forest Resources and Practices Act requires reforestation within seven years of timber harvest. Hence, inexpensive quick growing reforestation is critical for development of woody biomass energy in Alaska. Background Poplar, aspen, and willows grow prolifically in areas of Alaska. While spruce and birch have traditionally been the preferred varieties for burning because of their high energy content, fast growing poplar could offer an alternative when grown using sustainable biomass regeneration methods because of its faster regeneration rate. Prior to the awarding of this grant, trials by the DOF had found success using unrooted cuttings to revegetate reforestation sites near Willow. While the poplar planting techniques described in this report are not complex, they had never been applied to reforestation in Alaska, according to the grant application.

Table 1. BTU content is shown for various types of wood commonly found in Alaska.

Fuel Type Pounds per Energy Content Cord Birch 3485 23,600,000 Btu/cord White Spruce 2550 18,100,000 Btu/cord Black Spruce 2482 15,900,000 Btu/cord Balsam Poplar 2168 15,000,000 Btu/cord Cottonwood 2108 14,500,000 Btu/cord From: UAF Cooperative Extension2

According to the grant application, In North America the most common method for reforestation is transplanting seedlings that are reared in a nursery. This high cost method is not practical for a low value type of biomass such as poplars. Finding a successful method to plant un-rooted poplar cuttings could prove to be very beneficial for rural Alaska.

In addition to finding new methods to plant poplars in areas that have been deforested, the project participants also expressed interest in substituting poplars for ubiquitous willow growth in northern villages, both as a new heat source as well as a source of new economic opportunities through the production and use of local materials. In addition, they asserted that climate change may create future opportunities for poplar growth in regions where the tree has not thrived in the past.

1 Chapin, F. S., Oswood, M. W., Van Cleve, K., Viereck, L. A., & Verbyla, D. L. (Eds.). (2006). Alaska's changing boreal forest. Oxford University Press

2 http://www.alaskawoodheating.com/energy_content.php

Project Summary First Planting In March 2013, approximately 4000 stem cuttings (also called whips) were harvested from Balsam poplar (Populus balsamifera) growing in Palmer and Delta Junction, Alaska. Whips from a hybrid poplar variety (a cross of Populus deltoides x Populus balsamifera) were also obtained from Canada to compare with the Alaska harvested cuttings. All whips were stored in a freezer until late May when they were thawed and subsequently soaked in water for one week. The whips were planted at five sites in the MatSu Valley region and five sites in the Delta Junction region in mid-June 2013 (Table 2). This methodology was obtained from Muhlberg and Moore (1998) and DesRochers et al. (2004); the techniques have been found to be reasonably successful with poplar varieties on the Willow Experimental Forest near Wasilla, Alaska. Cuttings were also planted at UAF research stations in Palmer and Delta Junction.

The weather patterns during the summer of 2013 were unusually hot and dry, and high mortality was observed in the planted whips. By the spring of 2014, survival at most sites was only about 10%. Researchers considered the first year of the study a failure and started over in spring of 2014. The growing season temperatures experienced throughout the project are discussed later in this report.

Second Planting In 2014 poplar stems were obtained from Palmer and Delta Junction, Alaska, and two varieties from Canada. The varieties included both Populus balsamifera from Alaska and Alberta as well as a “Northwest” hybrid poplar of Populus balsamifera and Populus deltoids. Whips were harvested off the previous year’s growth from approximately twenty parent trees in dormant condition. The whips were 12-15 cm in length and were stored in plastic bags at -7°C. The two varieties of poplar cuttings from Canada were from Coast to Coast Reforestation in Edmonton, Alberta.

The same techniques used for the 2013 planting were used in 2014, and the whips were again thawed and soaked in water for 5-7 days before planting. In 2014, planting took place between May 30th and June 2nd. The sites are described in Table 2. Description of Sites Table 2. Site locations and descriptions3

Site Common Latitude Longitude Planted Ground Notes Name Site Name 2014 Temp Measured Delta Junction Sites Delta 2 Pogo Rd, 64.33442 -145.79233 Y mile 15 Delta 3 Pogo Rd, 64.30837 -145.99797 Y mile 7 Delta 4 Cummings 63.88655 -144.89753 Y Rd #2 Delta 5 Cummings 63.85403 -144.88271 Y X Logger gone from site when Rd #1 researchers returned to retrieve it. Delta 6 Pogo Rd 64.32445 -146.06202 Y mile 4 Delta Knight Rd 63.94393 -145.33639 Y Exp’tl (MP 1408) Farm

3 Site names are referred to in Table 1 as both “site name” and “common site name.” In various correspondence and reports from DOF, both titles were used, and both are included here for clarity. The site known as Delta 1 was omitted from this table for clarity since it was not planted in 2014. Matanuska-Susitna Valley Sites Zero Lake 61.66753 -149.80551 Y Sunset 61.65959 -149.61224 Y X Data logger vandalized as target practice and destroyed Willer 61.79843 -149.86813 Y Kash 1 Willer 61.83102 -149.85958 Y X September 2014, Hobo Kash 2 data logger gone at the southerly Willer Kash site Willer 61.84319 -149.82534 Y X Successful Data Logging Kash 3 Palmer 61.56947 -149.25192 Y Exp’tl Farm

Delta Junction Site Description The Delta Junction field sites are located in the legislatively designated Tanana Valley State Forest, all classified as forestry usage. All Delta Junction area sites have summer access and were sites of recently harvested primarily white spruce before this study. Sites labeled on the attached map as 4 and 5 are accessed from Cummings Road, leaving the Alaska Highway 28 miles southeast of Delta Junction, just east of the Gerstle River.

Sites 1, 2, 3 and 6 are accessed from the Pogo Road leaving the Richardson Highway 25 miles northwest of Delta Junction. Sites 1 and 2 are Jarvis-Chena Complex, a well-drained silt loam on flood plain landform. Site 3 is Salchaket silt loam, a well-drained silt loam on flood plain landform. Site 6 is Toghotthele-Fairbanks complex, well drained silt loam on hill landform. The nearest National Weather Service (NWS) station is Allen Army Airfield (PABI).

Delta Junction Farm The Delta Junction Field Research Site is located at Knight Road off the Alaska Highway at milepost 1407. Soil type is Gerstle-Moosehead complex, a well-drained very fine sandy loam on stream terrace landform. Nearest NWS weather station is Allen Army Airfield (PABI).

Figure 1. Delta Junction region site locations.

Mat-Su Valley Site Descriptions Matanuska-Susitna Valley field sites are on state land classified for forestry. This land was included in the proposed Susitna State Forest, introduced in the 2013 legislative session by Governor Parnell, HB 79 and SB 28. All Mat-Su sites have summer access. Descriptions of each site from the Department of Forestry are below:

Zero Lake: Unit 2D of Houston Zero Lake Road. Access is off the Parks Highway at milepost 60. The forest was recently harvested of birch and spruce. The topography is rolling with shallow ridges. The soil type is Estelle undulating-Disappoint complex, a well-drained silt loam on till plain landform. Nearest NWS station is Wasilla airport (PAWS). Sunset: Unit 2 of Sunset 2. Access is off Schrock Road from Wasilla. The forest was recently cleared of spruce. The terrain generally slopes to the north at three to seven percent. The soil type is Estelle undulating-Disappoint complex, a well-drained silt loam on hills and ridges landform. Nearest NWS station is Wasilla airport (PAWS). Willer-Kash 2 Unit 11 Tin #2. Same access and soil type as Willer-Kash 3 below. Willer-Kash 3 Units 56 & 61 Tin #3. Access is off the Willow Fishhook Road Highway about 5 miles from Parks Highway. The forest was recently harvested of birch and spruce. The topography is gently undulating with rolling hills. The soil type is Whitsol silt loam and Nancy Silt Loam, well drained on hills and ridges landform. Nearest NWS weather station is Talkeetna (PATK). Palmer Farm The Matanuska Experimental farm is located at 1509 S. Georgeson Drive, Palmer off Trunk Road. Soil type is Knik silt loam, a well-drained silt loam on outwash plain landform. Nearest NWS station is Palmer airport (PAAQ).

Figure 2. Mat-Su Valley Site locations

Approximately 50 cuttings of each variety were planted at each site as detailed in Table 3, and wire flags were used to mark each planting (Figure 3 and Figure 4). In addition, during the 2014 planting, whips were collected from Fairbanks and Glennallen and planted at a few sites to assess their survival and growth (May 24, 2016 personal communication with Val Barber).

Table 3. The number of cuttings of each species planted at each site in 2014.

Site Names Poplar Clone Variety Common Site Alternate Hybrid Alberta Palmer Delta Glennallen Fairbanks Name Site Name Delta Junction Pogo 15 Delta 2 50 50 20 50 Pogo 7 Delta 3 60 50 50 50 50 Cummings 2 Delta 4 65 60 53 51 35 50 Cummings 1 Delta 5 40 58 50 50 50 53 Pogo 4 Delta 6 32 5 21 31 Delta Farm 50 50 50 50 50 50 Mat Su Zero Lake Zero Lake 40 50 58 50 Sunset 50 50 50 50 50 50 Willer Kash 1 50 50 50 50 Willer Kash 2 50 50 50 51 Willer Kash 3 50 50 51 50 Palmer Farm 50 50 50 50 50 50

Figure 3. ACEP researcher Erin Whitney and Jeff Graham review the cuttings at a Mat-Su site.

Figure 4. Cuttings are shown leafing out at a sandy site located in the Delta Junction region. Data collection methodology Several types of data were collected as part of this project, including cutting survival and vertical growth, continuous soil temperatures, and meteorological data from nearby NWS weather stations. In September 2014, June 2015, and August 2015 all sites were checked for survival and height. Cutting Survival Table 4 and Table 5 show the survival rates of the various cuttings during the end of the summer of 2014 and 2015. In addition, Table 6 shows the change in height of the various cuttings during the study.

Table 4. Year 1 Survival Rates (2014)

Site Names Poplar Clone Variety Val’s Names CP Names Hybrid Alberta Palmer Delta Glennallen Fairbanks (Common (Site Site Name) Name) Delta Junction Cummings 1 Delta 5 95% 93% 66% 54% 4% 32% Cummings 2 Delta 4 100% 100% 53% 76% 14% 56% Pogo 15 Delta 2 76% 32% 25% 38% Pogo 7 Delta 3 92% 40% 14% 4% Pogo 4 Delta 6 72% 100% 14% 32% Delta Farm 76% 82% 52% 26% 6% 22% Mat Su Zero Zero Lake 18% 34% 40% 24% Sunset 32% 0% 76% 52% 16% 42% Willer Kash 1 2% 0% 22% 0% Willer Kash 2 92% 90% 0% 41% Willer Kash 3 84% 78% 39% 34% Palmer Farm 58% 52% 22% 8% 4% 20%

Table 5. Year 2 Survival Rates (2015)

Site Names Poplar Clone Variety Val’s Names CP Names Hybrid Alberta Palmer Delta Glennallen Fairbanks Average (Common (Site Site Site Name) Name) survival of four primary varieties Delta Junction Cummings 1 Delta 5 95% 57% 52% 14% 2% 8% 55% Cummings 2 Delta 4 80% 80% 43% 65% 9% 38% 67% Pogo 15 Delta 2 68% 18% 25% 24% 34% Pogo 7 Delta 3 50% 12% 0% 2% 0% 16% Pogo 4 Delta 6 0% 0% 0% 16% 4% Delta Farm 58% 52% 24% 22% 4% 12% 39% Mat Su Zero Zero Lake 10% 14% 29% 12% 16% Sunset 30% 0% 58% 38% 16% 20% 32% Willer Kash 1 0% 0% 0% 0% 0% Willer Kash 2 72% 84% 4% 35% 49% Willer Kash 3 64% 44% 16% 32% 39% Palmer Farm 24% 10% 6% 8% 2% 14% 12% Average 46% 31% 21% 22% 7% 15% Survival by Variety

Table 6. Change in heights (inches) of the cuttings between planting in the beginning of 2014 and the end of 2015.

Site Names Poplar Clone Variety Val’s Names CP Names Hybrid Alberta Palmer Delta Glennallen Fairbanks (Common (Site Site Name) Name) Delta Junction Cummings 1 Delta 5 -0.2 -0.7 0.0 1.6 -3.5 1.0 Cummings 2 Delta 4 -0.7 -1.1 1.2 1.1 -0.3 1.1 Pogo 15 Delta 2 8.3 1.9 1.5 3.1 0.0 0.0 Pogo 7 Delta 3 -0.9 0.2 0.5 0.0 0.0 Pogo 4 Delta 6? -8.4 1.0 0.0 0.0 Delta Farm -5.0 -3.1 0.3 -1.2 0.2 0.7 Mat Su Zero Zero Lake -0.6 0.9 2.6 0.9 0.0 0.0 Sunset 1.0 4.7 3.2 0.7 2.1 Willer Kash 1 -2.0 0.0 0.0 0.0 Willer Kash 2 5.4 2.9 16.0 1.8 0.0 0.0 Willer Kash 3 2.9 5.2 0.8 3.3 0.0 0.0 Palmer Farm 4.0 -0.4 0.0 2.5 -3.0 0.2 Average Change in Height 0.3 0.7 3.0 1.5 -0.5 0.4

Soil and Meteorological Conditions

Methodology for collecting soil temperatures At the beginning of the study in 2013, soil temperatures were monitored at 5 sites using Hobo brand data loggers. Each data logger was attached to four thermistors which were buried in the soil near the logger at various depths ranging from the surface to 35 cm below ground level with temperature measurements taken every two hours. Unfortunately, most of the data loggers were stolen or vandalized during the study, and only a limited amount of soil temperature data was collected.

In September 2014, researchers discovered that the Hobo data logger measuring soil temperature was gone at the Willer-Kash 2 and Cummings Road #1 (Delta 5) sites. In addition, another data logger at Sunset site had a bullet hole and was inoperable. Another soil data logger was not relocated by researchers after the 2013 season when the study areas were moved. In October 2014 the logger at Willer-Kash Site #3 (61.84319 -149.82534) was recovered, and the data was downloaded and analyzed. Because soil temperature was only successfully measured at one site, it is impossible to draw any relationships between soil temperatures to whip survival. Nevertheless, graphs showing soil temperature trends at the Willer-Kash Site #3 are presented in Figure 5.

Willer Kash #3 Site Ground Surface Temperatures F) ° 100

40 Temperature ( Temperature 20

0 May-13 August-13 November-13 March-14 June-14 September-14 December-14

Willer Kash #3 Site Ground Temperatures at 5 cm Depth

100 F) ° 80

0 Temperature ( Temperature May-13 August-13 November-13 March-14 June-14 September-14 December-14

Willer Kash #3 Site Ground Temperatures at 15 cm Depth

F) 100.00 °

80.00

60.00

40.00

Temperature ( Temperature 20.00

0.00 May-13 June-13 August-13 October-13 November-13 January-14 March-14 April-14 June-14

Willer Kash #3 Site Ground Temperatures at 30 cm Depth

100 F) ° 80

Temperature ( Temperature 0 May-13 August-13 November-13 March-14 June-14 September-14 December-14

Figure 5. Ground temperatures at the Willer Kash site measured at the surface down to 30 cm in depth. The graphs in figure 5 show that ground temperature below 5 cm in depth generally remained around 50°F during the summer starting in mid-May and dropped back to freezing in mid-October. Weather Station Data summary Weather during the summer of 2013 when the initial planting took place was warmer and dryer than normal and as explained above caused extreme mortality of the planted whips. Department of Forestry researchers reported that “cuttings are more sensitive to weather than rooted seedlings, and we needed near normal weather for reasonable survival” (Jeff Graham 22 August 2013, personal communication). As a result, the project was restarted in 2014 with improved success. Figures 6-8 show summaries of the temperatures from nearby weather stations during 2013-2015.

Weather data was collected at several sites near the testing to compare the 2013, 2014, and 2015 weather. Delta Junction temperature data was collected at the airport, approximately between The Cummings Road sites and the Pogo Mine Road sites. The Mat-Su data was collected from the Bentalit Lodge weather station and the Willow 3.6 SE weather station along the Parks Highway between the Sunset and the Willer Kash sites. In addition weather data from Talkeetna Airport was used to create a third data set.

Delta Junction

2013 Normal vs Average Monthly Summer 2013 Actual vs Average High Temperatures Daily High Temperatures 75 100 Average of 70

Actual High 90 F)

° Temp 65 80 Average of 60 Normal High 70

55 Temp 60 Temperature Temperature ( 50 50

45 40 6/1/2013 7/1/2013 8/1/2013 9/1/2013 Jun-13 Jul-13 Aug-13 Sep-13

2014 Normal vs Average Monthly Summer 2014 Actual vs Average High Summer Temperatures Daily High Temperatures Average of Actual 75 High Temp 100

70 Average of Normal F) ° High Temp 90 65 80 60 70 55 60

Temperature Temperature ( 50 50 45 40 Jun-14 Jul-14 Aug-14 Sep-14 6/1/2014 7/1/2014 8/1/2014 9/1/2014

2015 Normal vs Average Monthly Summer 2015 Actual vs Average High Summer Temperatures Daily High Temperatures Average of Actual 100 75 High Temp 90

70 Average of Normal F) ° High Temp 80 65 70 60 60 55

Temperature Temperature ( 50 50 45 40 6/1/2015 7/1/2015 8/1/2015 9/1/2015 Jun-15 Jul-15 Aug-15 Sep-15 Figure 6. Delta Junction high temperatures for the summer of 2013-2015 compared to average high temperatures. The average temperature is the defined by the NWS.

Willow

Summer 2013 Actual vs Average Summer 2015 Actual vs Average

Monthly High Temperatures 100 Daily High Temperatures 80 Average of Actual High Temp 90

F) ° 70 Average of 80 Normal High 65 Temp 70 60

Temperature Temperature ( 60 55

50 50 Jun-13 Jul-13 Aug-13 Sep-13 6/1/2013 7/1/2013 8/1/2013 9/1/2013

Summer 2014 Actual vs Average Summer 2015 Actual vs Average Monthly High Temperatures Daily High Temperatures 80 Average of Actual 100 High Temp

75 90 F)

° Average of Normal 70 High Temp 80 65 70 60

Temperature Temperature ( 55 60

50 50 Jun-14 Jul-14 Aug-14 Sep-14 6/1/2014 7/1/2014 8/1/2014 9/1/2014

Summer 2015 Actual vs Average Summer 2015 Actual vs Average Monthly High Temperatures Daily High Temperatures 80 Average of Actual 100 High Temp 75

F) 90

° Average of Normal 70 High Temp 80 65 70

60 Temperature Temperature ( 55 60

50 50 Jun-15 Jul-15 Aug-15 Sep-15 6/1/2015 7/1/2015 8/1/2015 9/1/2015

Figure 7. Willow area high temperatures for the summer of 2013-2015 compared to average high temperatures. The average temperature is defined by the NWS.

Talkeetna

Summer 2013 Actual vs Average Summer 2013 Actual vs Average Monthly High Temperatures Daily High Temperatures 80 100

F) Average of Actual ° 75 High Temps 90 70 Average of Normal 80 65 High Temps 70 60 Temperature Temperature ( 55 60 50 50 Jun-13 Jul-13 Aug-13 Sep-13 6/1/2013 7/1/2013 8/1/2013 9/1/2013

Summer 2014 Actual vs Average Summer 2014 Actual vs Average Monthly High Temperatures Daily High Temperatures

80 Average of Actual 100 F)

° High Temps 75 90 Average of Normal 70 High Temps 80 65 70 Temperature Temperature ( 60 55 60 50 50 Jun-14 Jul-14 Aug-14 Sep-14 6/1/2014 7/1/2014 8/1/2014 9/1/2014

Summer 2015 Actual vs Average Summer 2015 Actual vs Average Monthly High Temperatures Daily High Temperatures

80 Average of Actual 100 High Temps 75

F) 90 ° Average of Normal 70 High Temps 80 65 70 60

Temperature Temperature ( 55 60 50 50 Jun-15 Jul-15 Aug-15 Sep-15 6/1/2015 7/1/2015 8/1/2015 9/1/2015

Figure 8. Talkeetna area high temperatures for the summer of 2013-2015 compared to average high temperatures. The average temperatures are defined by the NWS.

Table 7. The normal average high temperatures are shown along with the monthly average high temperatures during the summers of 2013-2015.

Delta Junction Willow Talkeetna Average 2013 2014 2015 Average 2013 2014 2015 Average 2013 2014 2015 June 67 74 63 68 67 76 65 71 67 74 63 69 July 69 70 66 68 69 75 72 73 68 71 69 68 August 64 67 65 60 65 67 67 72 65 65 65 67

** Actual monthly average high temperatures are within 1 degree of historical monthly high temperatures ** Actual monthly average high temperatures are more than 1 degree below historical monthly high temperatures ** Actual average high temperatures are between 1 and 3 degrees above monthly average high temperatures ** Actual average high temperatures are greater than 3 degrees above monthly average high temperatures

In Figures 6-8 above as well as Table 7, temperatures from Willow, Talkeetna, and Delta Junction provide a representative sample from the section of the state where the study took place. The temperature data support the assertion made by the Department of Forestry researchers that the summer of 2013 was abnormally hot. It also appears the Willow testing area was slightly hotter than normal in 2015. On the other hand, during the summer of 2014, when the new whips were planted, the area experienced more average temperatures and likely provided a good sample climate for this study.

Findings and Conclusions Survival rates between the various sites varied significantly as part of this study ranging from 0% survival at the Willer Kash 1 site to 67% survival at the Cummings 2 site. At all sites except the Sunset Site, the Alberta clone and the Hybrid variety had the highest survival rates. It appears that the Canadian varieties of Poplar could be the most promising for reforestation and biomass projects. In reference to the survival rates from the Hybrid and Alberta clones, Department of Forestry researchers indicated that “facilitated migration may be the way to go” (Valerie Barber, Personal Communication 24 May 2016). It should be emphasized that the change in height of the Canadian Poplar was slightly less than the Alaskan varieties. A longer term study would likely be necessary to determine the growth differences with more confidence.