Source: ISCA TECHNOLOGIES, INC. submitted to NRP
"SHIELDING SPRUCE AND DOUGLAS FIR TREES FROM BARK BEETLE ATTACK"
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
SMALL BUSINESS GRANT
Reporting Frequency
Annual
Accession No.
1024683
Grant No.
2020-33530-33224
Cumulative Award Amt.
$650,000.00
Proposal No.
2020-08019
Multistate No.
(N/A)
Project Start Date
Sep 1, 2020
Project End Date
Aug 31, 2022
Grant Year
2020
Program Code
[8.1]- Forests & Related Resources
Recipient Organization
ISCA TECHNOLOGIES, INC.
2060 CHICAGO AVE STE C2
RIVERSIDE,CA 92507
Performing Department
(N/A)
Non Technical Summary
ISCA Technologies will further develop and optimize MCH Repel DFB and MCH Repel SB, two safe and effective semiochemical-based solutions to manage Douglas-fir beetle (DFB), Dendroctonus pseudotsugae, and spruce beetle (SB), D. rufipennis, two of the most damaging forest pests in western North America. DFB is a leading killer of Douglas-fir from northern Mexico to southern Canada, with infestations occurring after wildfires or windstorms, which produce widespread tree mortality and damage and consequently an abundance of beetle host material. DFB impacts are being exacerbated by climate change, which increases beetle survival during the winter and also puts more stress on trees. SB is the leading cause of mortality among mature spruce trees from Alaska to Arizona, destroying ~333-500 million board feet of timber annually. Such extensive tree mortality depletes timber supplies, increases fire frequency and severity, and disrupts forest management planning and operations. Current control tactics for DFB and SB are limited to silvicultural treatments to improve forest health and increase tree stand vigor, strategic removal of infested trees, preventative single-tree treatments using large quantities of toxic insecticides, and hand application of plastic dispensers containing the anti-aggregation pheromone, 3-methylcycolhex-2-en-1-one (MCH), which have proven unreliable for control of SB.In this Phase II project, ISCA will finalize the development and commercialize two non-toxic repellent products, MCH Repel DFB and MCH Repel SB, to protect trees and forests from DFB and SB. Both products will comprise thick, flowable long-lasting formulations amenable to mechanical application, combining MCH with a biodegradable controlled-release matrix, SPLAT® (Specialized Pheromone & Lure Application Technology). MCH Repel SB will include three additional repellent semiochemicals [acetophenone, (E)-2-hexen-1-ol, and (Z)-2-hexen-1-ol] to improve its efficacy against SB. These products will release biologically active doses of repellents for up to 4 months, preventing beetle mass attacks and providing season-long protection of susceptible trees. Phase I studies demonstrated that ISCA's prototype MCH Repel DFB biodegradable formulation protects individual Douglas-fir trees and stands from DFB to an equivalent degree as MCH bubblecaps, which release MCH through porous plastic pouches, but without the costly need to retrieve the plastic units at the end of the field season. In a field trial in Wyoming, MCH Repel SB was superior to bubblecaps in suppressing SB infestations. Phase II studies will build on Phase I successes by developing operational formulations suitable for commercialization, with the necessary validation of efficacy data from field trials in several locations in western North American forests.Our objectives for PII studies will be to: 1) Develop, optimize, characterize, and standardize operational formulations of MCH Repel DFB & MCH Repel SB suitable for commercialization. 2) Validate efficacy of MCH Repel DFB and foster technology transfer to end users by conducting operational field trials in western North American Douglas-fir forests. 3) Elevate MCH Repel SB to the same developmental stage as MCH Repel DFB by accelerating small-plot experiments in Alaska and the lower 48 states. 4) Validate efficacy of MCH Repel SB and foster technology transfer by conducting operational field trials in western North American spruce forests. 5) Involve stakeholders in problem identification and implementation of results. Deliverables from Phase II will be optimized, scientifically validated operational formulations of MCH Repel DFB and MCH Repel SB for commercial use throughout western North American forests. Users of both products in the US and Canada will be government forest health professionals, industrial foresters, private landowners, farmers, ranchers, arborists, citizens associations, and recreational managers.
Animal Health Component
50%
Research Effort Categories
Basic
(N/A)
Applied
50%
Developmental
50%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
21106101130100%
Knowledge Area
211 - Insects, Mites, and Other Arthropods Affecting Plants;

Subject Of Investigation
0610 - Conifer forests of the North;

Field Of Science
1130 - Entomology and acarology;
Goals / Objectives
There are five main objectives for Phase II: Task 1. Develop, optimize, characterize, and standardize operational formulations of MCH Repel DFB and MCH Repel SB suitable for immediate commercialization. Task 2. Validate efficacy of MCH Repel DFB and foster technology transfer to end users by conducting operational field trials in western North American Douglas-fir forests. Task 3. Elevate MCH Repel SB to the same developmental stage as MCH Repel DFB by accelerating small-plot experiments in Alaska and the lower 48 states. Task 4. Validate efficacy of MCH Repel SB and foster technology transfer by conducting operational field trials in western North American spruce forests. Task 5. Involve stakeholders in problem identification and implementation of results. Deliverables from Phase II will be optimized, scientifically validated operational formulations of MCH Repel DFB and MCH Repel SB.
Project Methods
Task 1: Develop, optimize, characterize, and standardize operational formulations of MCH Repel DFB and MCH Repel SB suitable for immediate commercialization.Microencapsulated AIs (unformulated) will be subjected to longevity trials,by being hung on a wire shelf with a twist tie passed through a hole punched in the filter paper. A fan will be placed in front of the samples so that all samples receive similar air flow. Samples will be prepared for collection at 1, 4, 7, 14, 21, 28, 60, 60, and 120-day intervals to measure initial flash-off rates of the microencapsulated AIs.Task 2: Validate efficacy of MCH Repel DFB and foster technology transfer by conducting operational field trials in western North American Douglas-fir forests. Working with Dr. Chris Fettig and his USFS colleagues, ISCA will locate two to six small problem sites (up to 50 ha in size) within forested areas in which mature Douglas-fir (>30 cm DBH) comprises >80% of the tree species composition and where maintaining forested cover is desired. Examples include campsites, recreational areas, sensitive ecological zones, small parks, national monuments, private land holdings, farm or ranch woodlots, sites with prime wildlife features (e.g., owl nesting sites, ungulate overwintering areas, overwintering bear dens), sites providing valued aesthetic viewing (e.g., from a well-used highway), and forested rural communities. DFB infestation will constitute <20% of the available trees or populations will be expected to emerge from disturbed sites such as infested blowdown and threaten the site to be protected. Each problem site will be unique. For example, infested trees may remain in place or may have been removed during the previous fall and winter, access to the public or grazing cattle may be permitted or denied, or applications of carbaryl may have been made in one or more previous years. The critical criterion will be that the threat of DFB attack must be sufficiently high that one or more of the above attributes is in peril.Evaluation. Operational trials will be evaluated by total tree counts and stem mapping after DFB flight. A team leader with a hip chain will walk a compass line and record data. Flankers on either side will cover bands up to 25 m wide. Orienting to the leader, they will determine the approximate position of each attacked and unattacked tree using 2.5 m-long poles as measuring sticks. Attacked trees will be identified by the presence of beetle frass (boring dust) around the root collar and lodged in cobwebs and bark scales, resin bleeding around entrance holes if present, and early signs of crown fade. A portion of bark will be removed with an axe from trees showing external symptoms, and the inner bark (phloem tissue) will be examined for the presence of egg and larval galleries and general browning, all signs of successful attack. A small V-shaped axe cut will be made into the bark of questionable trees; if the phloem is white and pulpy, the tree will be classed as unsuccessfully colonized or unattacked, depending on whether signs of unsuccessful attack can be found. The team leader will plot the position of each tree on waterproof graph paper. Experience indicates that hand plotting is just as reliable as GPS and is fail safe. At 25-m intervals along each transect a diameter tape will be used to determine the DBH of the nearest Douglas-fir. The DBH of each successfully attacked tree will also be taken. Employing total tree plots will eliminate the need for fixed or variable radius plots to determine stocking density and enable investigators to determine the distribution of infested trees and evaluate other factors such as edge effects.Task 3. Elevate MCH Repel SB to the same developmental stage as MCH Repel DFB by accelerating small-plot experiments in Alaska and the lower 48 states. The remarkable success of MCH Repel SB in protecting individual spruce trees from SB attack in Wyoming (Table 3) was a game changer for employing SPLAT technology against SB. To exploit this opportunity maximally, ISCA will pursue Tasks 3 and 4 concurrently. For Task 3, small plot experiments will be conducted in Alaska, the lower 48 states, and Canada.?Task 4. Validate efficacy of MCH Repel SB and foster technology transfer by conducting operational field trials in western North American spruce forests. This task will be pursued with almost identical methodology and evaluation as for DFB in Task 2. Exceptions are that spruce sites are characteristically at higher elevation, have steeper slopes and are more brushy, SB has a 2-year life cycle with crown fade only occurring in the second year, access may be more difficult than in Douglas-fir stands, and field crews can be expected to feed several thousand more mosquitoes and biting flies.Task 5. Involve stakeholders in problem identification and implementation of results. We have already reached out to various stakeholder groups interested in the proposed technology. We have secured the cooperation of several research partners to participate in Phase II field trials, including Dr. Fettig; Sky Stephens, Forest Entomologist with the US Forest Service; Marnie Duthie-Holt, Regional Entomologist with the Ministry of Foreign Lands, Natural Resources, and Rural Development (British Columbia); and Jason Moan of the Alaska Department of Natural Resources, Division of Forestry. John Vanderhart, President and CEO of Forestry Distributing, has also expressed great interest in the commercial potential of MCH Repel DFB and SB (see letters of support). Our interactions with North American forestry experts, especially with Dr. Borden, have provided invaluable input on the technical and practical requirements MCH Repel products must meet in order to be a viable solution for the broadest possible customer base. One aspect wherein this input has been particularly constructive is the question of which application method(s) would be best suited to these repellents. For PII trials, we will package MCH Repel DFB/SB in caulking tubes (to be used in caulking guns), which we have learned are fairly simple to use in many forestry management programs. However, as we move through PII studies, we will continue to seek end-user input on how application methods could be improved, including exploring the potential of paintball technology to apply MCH Repel point sources, which could make applications from the ground easier and faster, as well as aerial application technologies. ISCA has already tested other SPLAT formulations similar to MCH Repel applied using drones or fixed-wing aircraft, and in some cases, large-scale or commercial aerial applications have already been made. If such an application method proves feasible for MCH Repel DFB and SB, it could allow for treatment of much larger tracts of land more quickly, as well as overcoming the challenge of access to remote areas.?

Progress 09/01/20 to 08/31/22

Outputs
Target Audience:Forest resources support the economic and social well-being of US citizens, providing clean water and air, timber supplies, energy and mineral resources, a home to native wildlife and fisheries, and a plethora of employment and recreational opportunities. They are especially vital to the health of US rural communities and economies [133]. Infestations and mortality caused by Douglas-fir beetle (DFB),Dendroctonus pseudotsugae, and spruce beetle (SB),D. rufipennis, are an increasing threat to North American forests, worsened by climate change-induced drought, which reduces trees' ability to cope with attacks. In addition to mortality caused by bark beetle attack, infestations also increase the risk of wildfires by increasing the amount of dead, dry timber among standing forests. Ever-changing forest conditions and currentclimatetrendswill likely result in the continued expansion and impact of bark beetle populations across thecontinentalUS. The threat posed by bark beetle infestations is also exacerbated by a lack of viable control options, particularly at larger scales where insecticide-based tactics would be environmentally hazardous and economically unfeasible. Through the course of this project, ISCA has maintained a close partnership with the US Forestry Service, who have been invaluable in proceeding with the development of the MCH semiochemical solutions. ? Changes/Problems:Covid-19 lockdown and following supply chain issues had hampered some of our efforts to go to the field with our USDA Forestry partners, but at the same time it allowed us to further explore and analyze the data obtained for MCH project in the 2019 and report it, and publish it. We have also been able to connect and better pre-plan the 2021 field season with our colleagues from California, Alaska, Utah and Wyoming. What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? There are five main objectives for this Phase II project: Task 1:Develop, optimize, characterize, and standardize operational formulations of MCH Repel DFB and MCH Repel SB suitable for immediate commercialization. We have been working on different formulations in the lab and communicating with our collaborators to finalize a pair of stable and uniquely tailored SPLAT formulations that combine MCH with ISCA's SPLAT matrix, and in the case of MCH REPEL SB, additional volatile kairomones. The formulations are designed to allow ISCA to use a similar method of large-scale production as one of its other flagship products, SPLAT Verb. The formulations were also designed to maintain a similar viscosity as SPLAT Verb, to minimize the impact of training end-users by keeping the same application methods as SPLAT Verb. Task 2:Validate efficacy of MCH Repel DFB and foster technology transfer to end users by conducting operational field trials in western North American Douglas-fir forests. Although the Covid-19 lockdown has hampered some of our efforts to go to the field with our USDA Forestry partners, but at the same time it allowed us to further explore and analyze the data obtained for MCH project in the 2019. Our conclusions were the following: 1) Data from Wyoming were very promising, and warrant pursuing registration of MCH + GLV for spruce beetle. Further evaluations should include confirmation of the most promising treatments for protection of individual trees (2020), determination of the range of inhibition of these treatments (2020, see Fettig et al. 2015 for design), and field assays for protection of small-scale plots (2021, spacing to be determined based on range of inhibition studies). 2)Trials were repeated in Alaska in 2022 with much more promising results (see Task 4). This isolation due to COVID-19 lockdown allowed the group of collaborators to be extremely productive with publications, especially our collaborators lead by Dr. Fettig initiative. Task 3:Elevate MCH Repel SB to the same developmental stage as MCH Repel DFB by accelerating small-plot experiments in Alaska and the lower 48 states. In general, the study has progressed as outlined in the original proposal, with the following exceptions: (1) In Alaska and Wyoming sample sizes were reduced (from 25 to 20 and 13, respectively) due to limitations in the number of unattacked hosts that were available for treatment. (2) We were unable to collect the final data in Wyoming due to restrictions concerning travel and COVID-19. Task 4:Validate efficacy of MCH Repel SB and foster technology transfer by conducting operational field trials in western North American spruce forests to determine the optimal semiochemical repellent blend. We assessed the efficacy of the most promising blends of SPLAT® MCH and nonhost volatiles for protecting white spruce in Alaska and Engelmann spruce in Utah in 2021-2022, as well as in British Columbia in 2021. In British Columbia in early 2021, the product was applied to single trees in an area with historical Dendroctonus rufipennis presence. In addition to untreated control trees, SPLAT MCH was paired with three other blends of non-host semiochemical volatiles to evaluate the optimal repellent blend. The treated and untreated trees were monitored throughout the follow year and into 2022 for signs of infestation. All formulation blends performed significantly better than the control trees, with 92% of the control attacked and between 0-20% of treated trees infested. In addition to monitoring the health of the single trees to which the formulations had been applied, trees in an 11m radius (0.1 acres) were also inspected for signs of infestation throughout the trial. Two of the treatments showed significantly lower infestation rates in these "halo" areas. (Figure 1). Figure 1: Dendroctonus rufipennis attacks in 2021 single tree study, British Columbia. CON= Control, MCH, GLV, OCT, AKB = Treatments 1, 2, 3, 4, varying semiochemical blends. These promising initial results were repeated in a trial in Utah with the same single-tree protocol, minus the monitoring of the 11m radius surrounding the selected trees. The best performing formulation in the Utah trial was the MCH+Acetophenone+GLVs, which was not one of the treatments in the BC trial the year prior, but the MCH+AKB blend also performed significantly better than the control and was also a top performer in the British Columbia trial the year before. (Figure 2). Figure 2: Dendroctonus rufipennis attacks in 2022 single tree study, Utah. SPLAT MCH +ACE+GLVs and SPLAT MCH+AKB showed significantly lower infestation rates than the baited controls. It was determined that an undetermined percentage of the initially chosen trees may have been already suffering from an early infestation, as the season was early, and supply chain issues delayed the delivery of the formulations on site. This may explain the lower performance of the remaining two treatments in comparison to the previous year's trial. Repellents were reapplied for further evaluation in 2023. A trial in Alaska the same year (2022) also displayed promising results, which was established on the Chugach National Forest in Southcentral Alaska. Repellents were deployed in May. Spruce beetle colonization status for all treated trees, and for all neighboring spruce trees (within an 11.3-m radius), were assessed in August. 100 Lutz spruce trees with no signs of spruce beetle attacks and ≥20.3 cm diameter at breast height were selected and randomly assigned to one of five treatements: (1) SB lure (SBL) only (baited untreated control); (2) SBL + SPLAT® MCH + acetophenone + [(E)-2-hexen-1-ol + (Z)-2-hexen-1-ol]; (3) SBL + SPLAT® MCH + linalool + β-cayophyllene + (Z)-3-hexen-1-ol; (4) SBL + SPLAT® MCH + 1-octen-3-ol; (5) SBL + SPLAT® MCH + acetophenone + [(E)-2-hexen-1-ol + (Z)-2-hexen-1-ol] + linalool + β-caryophyllene + (Z)-3-hexen-1-ol + 1-octen-3-ol. Along with defining and treated the selected trees, as in the study in British Columbia, the "halo" effect of the formulations was also monitored. Tenth-acre circular plots (11.3-m radius) were established with each treated tree as the center. All trees ≥10.2 cm dbh within these plots were identified, measured, and recorded. The initial treatment occurred in May 2022, and the trees will be re-evaluated in 2023 for final mortality assessments by observing crown fade, but initial observations show all treatments performing significantly better than the control. Task 5:Involve stakeholders in problem identification and implementation of results. Our research team includes representatives from the Alaska Department of Natural Resources, Forest Health Protection, Pacific Southwest Research Station, and semiochemical industry with researchers from ISCA Technologies Inc. Results were delivered in verbal presentations at technical and scientific meetings, and in written formats in PIAP reports and a technical paper published in the Journal of Economic Entomology, as well as others listed above. All products will adhere to Section 508 standards. We will continue to work with the Alaska Division of Forestry and University of Alaska-Fairbanks Cooperative Extension Service to provide the public with the latest information concerning options for management of spruce beetle. The website "Spruce Beetle in Alaska's Forests" (www.alaskasprucebeetle.org) will also provide an active conduit for technology transfer.

Publications


    Progress 09/01/20 to 08/31/21

    Outputs
    Target Audience:With this project, ISCA Technologies seeks to develop and optimize MCH Repel DFB and MCH Repel SB, two safe and effective semiochemical-based solutions to manage Douglas-fir beetle (DFB), Dendroctonus pseudotsugae, and spruce beetle (SB), D. rufipennis, two of the most damaging forest pests in western North America. DFB is a leading killer of Douglas-fir from northern Mexico to southern Canada. DFB infestations typically occur after disturbances such as wildfires or windstorms, which cause widespread tree mortality and damage and consequently produce an abundance of beetle host material. The impacts of DFB infestation are being exacerbated by climate change, which increases beetle survival during the winter and puts more stress on trees. SB is the leading cause of mortality among mature spruce trees from Alaska to Arizona, destroying ~333-500 million board feet of timber annually. Such extensive tree mortality depletes timber supplies, increases fire frequency and severity, and disrupts forest management planning and operations. Current control tactics for DFB and SB are limited to silvicultural treatments to improve forest health and increase tree stand vigor, strategic removal of infested trees, preventative single-tree treatments using large quantities of toxic insecticides, and hand application of plastic dispensers containing the anti-aggregation pheromone, 3-methylcycolhex-2-en-1-one (MCH), which have proven unreliable for control of SB. Changes/Problems:Covid-19 lockdown has hampered some of our efforts to go to the field with our USDA Forestry partners, but at the same time it allowed us to further explore and analyze the data obtained for MCH project in the 2019 and report it, and publish it. We have also been able to connect and better pre-plan the 2021 field season with our colleagues from California, Alaska, Utah and Wyoming. What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?Task 5:Involve stakeholders in problem identification and implementation of results. Our research team includes representatives from the Alaska Department of Natural Resources, Forest Health Protection, Pacific Southwest Research Station, and semiochemical industry with researchers from ISCA Technologies Inc. Results will be delivered in verbal presentations at technical and scientific meetings, and in written formats in PIAP reports and a technical paper published in the Journal of Economic Entomology. All products will adhere to Section 508 standards. We will continue to work with the Alaska Division of Forestry and University of Alaska-Fairbanks Cooperative Extension Service to provide the public with the latest information concerning options for management of spruce beetle. The website "Spruce Beetle in Alaska's Forests" (www.alaskasprucebeetle.org) will also provide an active conduit for technology transfer. What do you plan to do during the next reporting period to accomplish the goals?Our schedule is the following: 1. Development and preparation of MCH formulations and field materials, packaging and shipping to test areas (September 2020-May 2021) 1. Trapping assays (May-June 2021) 2. Tree protection studies (June 2021-July 2022) 3. Presentation at Western Forest Insect Work Conference (May 2022) 4. Data analyses and submission of peer-reviewed publication (July-September 2022)

    Impacts
    What was accomplished under these goals? There are five main objectives for this Phase II project: Task 1: Develop, optimize, characterize, and standardize operational formulations of MCH Repel DFB and MCH Repel SB suitable for immediate commercialization. We have been working on different formulations in the lab and communicating with our collaborators in order to be ready for this year's field trials in California, Alaska, Utah and Wyoming. Task 2: Validate efficacy of MCH Repel DFB and foster technology transfer to end users by conducting operational field trials in western North American Douglas-fir forests. Although the Covid-19 lockdown has hampered some of our efforts to go to the field with our USDA Forestry partners, but at the same time it allowed us to further explore and analyze the data obtained for MCH project in the 2019. Our conclusions were the following: 1) Data from Wyoming were very promising, and warrant pursuing registration of MCH + GLV for spruce beetle. Further evaluations should include confirmation of the most promising treatments for protection of individual trees (2020), determination of the range of inhibition of these treatments (2020, see Fettig et al. 2015 for design), and field assays for protection of small-scale plots (2021, spacing to be determined based on range of inhibition studies). 2) Data from Alaska were discouraging. Further evaluations in Alaska should involve conducting trapping bioassays to confirm levels of inhibition of the most promising treatments (and additional inhibitors/repellents) prior to revisiting any efforts to protect individual trees. Methods published by Fettig et al. (2005) should be use for rapid acquisition of data via re-randomization of treatments on a daily basis. Ideally two 10-d assays (first in late May, second in mid-June) should be executed. Task 3: Elevate MCH Repel SB to the same developmental stage as MCH Repel DFB by accelerating small-plot experiments in Alaska and the lower 48 states. In general, the study has progressed as outlined in the original proposal, with the following exceptions: (1) In Alaska and Wyoming sample sizes were reduced (from 25 to 20 and 13, respectively) due to limitations in the number of unattacked hosts that were available for treatment. (2) We were unable to collect the final data in Wyoming due to restrictions concerning travel and COVID-19. Final procurement has been rescheduled for June 2021.Final data procurement for Wyoming and Alaska has been rescheduled for June 2021 due to COVID-19. Task 4: Validate efficacy of MCH Repel SB and foster technology transfer by conducting operational field trials in western North American spruce forests. Final data procurement for Wyoming and Alaska has been rescheduled for June 2021 due to COVID-19. First, we will assess levels of spruce beetle inhibition for novel blends of SPLAT® MCH and nonhost volatiles in trapping assays in Alaska and Utah in May-June 2021. Second, based on results from these trapping assays, we will assess the efficacy of the most promising blends of SPLAT® MCH and nonhost volatiles for protecting white spruce in Alaska and Engelmann spruce in Utah in 2021-2022. In Utah, we will also assess lower rates of the most promising blend identified in R10-2019-SPLAT MCH (SPLAT® MCH + GLV) for tree protection. Trapping assays: (1) SB lure (SBL) only (2) SBL + SPLAT® MCH (3) SBL + SPLAT® MCH + 1-octen-3-ol (4) SBL + SPLAT® MCH + acetophenone + [(E)-2-hexen-1-ol + (Z)-2-hexen-1-ol] (5) SBL + SPLAT® MCH + linalool + β-cayophyllene + (Z)-2-hexen-1-ol (6) SBL + SPLAT® MCH + exo-brevicomin + endo-brevicomin + ipsdienol (7) SBL + SPLAT® MCH + limonene + verbenone Each treatment will be replicated 30 times (3 replicates/day X 10 days) Tree protection studies: Based on results from above, the most promising treatments will be evaluated using standard protocols for individual tree protection (see PIAP-R10-2019-SPLAT MCH). Each treatment will be replicated 25 times.

    Publications