1. Chris JK MacQuarrie & Lee Humble
Assessment of systems approach for the phytosanitary treatment of wood infested with invasive wood borers
Chris JK MacQuarrie & Lee Humble
Canadian Forest Service Great Lakes Forestry Centre & Pacific Forestry Centre
@cmacquar

2. Good afternoon. My presentation today is about some work we’ve been doing over the past year looking at revising phytosanitary treatment methods for exported wood products from Canada, using Emerald ash borer as a model system.

3. Project Sublethal effects?
In this study we want to see if we can elicit sublethal effects in woodboring beetles with kiln treatments that are done as part of the lumber production process.
We’ve completed the 1st year of this study using slabs of EAB and while we were not able to elicit sub-lethal effects we have bracketed the temperatures we need to trial in the 2nd year
The motivation for this work comes from two places: - The move by the CFIA and other regulatory bodies to a systems approach. Here the systems approach is one where we consider all the activities during lumber production and the reduction of risk in wood products from wood borers
The hope that we can revise wood treatment standards for ash and other species to save energy required in the production process
The reason we are interested in sublethal effects is that the present standards allow for procedures that inactivate pests or render them infertile then the wood can be considered safe for import and export. If we can show that treating wood to a reduced temperature still renders the target infertile this could mean savings for wood producers.
Our target taxa for this study is the EAB. For 2 reasons – ash is still a somewhat important export species for Canada, and 2 we need a species where we can access large numbers of individuals in wood that we can then treat. Unfortunately EAB meets that criteria

4. Spread in Canada
This is the regulated area for EAB in Canada. We have access to lots of infested ash in S. Ontario for this experiment.
The trees for this experiment came from Southwestern Ontario, we did the work at the Great Lakes Forestry Centre in Sault Ste. Marie, Ontario. Except for the kin treatments. These were done at the FPInnovations facility in Quebec City.

5. Background
Previous work on the effect of heat treatment on EAB viability

6. Background
Previous work on the effect of heat treatment on EAB viability

8. Experiment
We cut the trees in Feb of Transported to GLFC then slabbed on a portable sawmill, took them to QC, kilned the insects, brought them back to GLFC, put them into emergence chambers, collected everything that came out and then reared them on foliage. We also then dissected all the slabs to see what came out.

9. Results - kilning
Our target temperatures for the treatments were as indicated
Our four treatments were an untreated control, 48 C, 56 C and 71 C for 30 minutes
Temperatures were recorded in the slabs using thermocouples inserted into the slab. These data are what was recorded in the slab by the thermocouples.

10. Results - emergence
We had essentially no emergence from the 56 C and 71 C slabs, some from the test boards (these were slabs we used to set up the kiln runs and represent 1-offs that we emerged anyway)

11. Results - emergence
We see no statisticaly significant difference between controls and 48 C in the number of emerged males or females

12. Are all treatments created equal?
Plot showing total emergence content in each treatment

13. Results - size
We next examined the size of these insects to see if there were effects of the heat treatment on their use of energy reserves during pupation and also found no effect on size

14. Results - survival
We then reared all the insects we found on ash foliage under controlled conditions in the laboratory. Here we did both multiple pair matings where we held 3 pairs of EAB in 1 rearing cup, and cups where we had just on pair. This was also a bit more efficient for some pairs.
In the single pair matings we used EAB reared from logs to make sure that females were mated with viable males for the next part of the experient. So the survivorship here are actally of males from bolts, not from the treated slabs. Bt there is still no effect on survivorship.

15. Results - fecundity

17. Pending
Fat content analysis
Emergence from cants

18. Next phase Repeat experiments between
With the milling experiment we want to quantify reductions in EAB abundance that occur prior to kilning. Ideally what we’ll be able to show is how the risk profile changes during the lumber production process. What’s really cool about this 2nd phase is that as far as we can determine no one has ever tried to do this particular experiment. If we can pull it off it will be really interesting to quantify this process.
Repeat experiments between
48 and 56 C
Effect of milling on pest risk reduction