Slowing Down the Spruce Budworm (Ask NRCan)

- Joël Houle
Welcome, everyone, to a bonus episode of Ask NRCan! I’m your host, Joël Houle, and this is our podcast series where we sit down with our experts to talk about the work that we do here at Natural Resources Canada (or NRCan for short).We typically only do one episode of Ask NRCan per month, but this is a busy time of year for our department, and we have a lot of interesting science that is relevant right now that we want to share with you. One specific topic that we couldn’t wait to cover is the spruce budworm — a notorious forest pest that has been causing havoc in recent years in Eastern Canada. For those of you who are new to the show, we call this series “Ask NRCan” because we want to hear from you. The purpose of the show is to share with you not only the type of science that we do, but also the reasons why we do it and how they relate to your life. So, at the end of the episode, if you have any questions on today’s topic, head to Twitter and tweet at us using the hashtag “#AskNRCAN”. Our experts will do their best to answer all relevant questions. We usually release an episode of Ask NRCan on the first Tuesday of each month, so make sure to subscribe so you don’t miss an episode. Ok, let’s meet our guest! My guest today is Rob Johns from the Canadian Forest Service in Fredericton, New Brunswick. Rob, thank you for joining us!

- Rob Johns
Thank you Joel for inviting me.

- Joël Houle
Can you start by telling us about the spruce budworm and why it's such a problem in eastern Canada?

- Rob Johns
Yeah sure, I mean spruce budworm is the major defoliating pest throughout Canada, throughout northeastern North America. It's especially a problem I think in part because we have such dense forests of spruce and fir and that's the preferred host for the insect. And essentially what the insect does is it it tends to be very low densities over long periods of times for decades and then suddenly these outbreaks will appear. The insects will, it's a moth by the way, and the insects will start to feed on the new developing foliage. This puts stress on the trees and if you get five or six years of that it can start killing the trees. And yeah so when you have an industry or sort of a population that is so reliant on forest for some spruce and fir like we are in Eastern Canada an insect like that, that defoliates and kills those trees can have a huge impact on the local economy.

- Joël Houle
So what is Natural Resources Canada doing to address this issue?

- Rob Johns
So I mean this has been a long standing question is how do you manage spruce bud worm? And one of the things that Natural Resources Canada, we have these scientists that have been working on spruce budworm probably for the last 50 years or so trying to figure out how we manage that. So currently what we've been doing a big part of this work has been to try to understand what actually causes these outbreaks to arise and trying to use that to develop a strategy to actually sort of mitigate that that damage.  And one of the ways that we've come up with recently some of our groups are our colleagues from here and in Eastern Canada at the Canadian Forest Service is this so-called early intervention strategy. And essentially this is aimed at trying to slow the spread of this outbreak along the leading edge of where it's expanding. And the idea is to prevent it from filling the entire area that it often does. You know, during the previous outbreak, you're talking about most of Eastern Canada was defoliated by spruce budworm. We're trying to avoid that. We're trying to keep constrained to where it is. Right now we're just centred on the north shore of Quebec.

- Joël Houle
So I've read online something called the Healthy Forest Partnership and it appears that that's something that NRCan is involved with. Who are these partners and what type of organizations and government bodies are you working with?

- Rob Johns
Right, so when we first started trying to figure out how we were going to address this current spruce budworm outbreak, this partnership, which as you alluded to, that the healthy forest partnership kind of came together somewhat fairly organically. It's a group of industry, universities, of course Natural Resource Canada scientists, provincial governments are a big part of this and this is for all of the Atlantic provinces. PEI, Nova Scotia, Newfoundland, New Brunswick. Maine is also a part of this of course they're apart, they're right next to us and so they're apart of this initiative as well. And really what we all sort of have different roles as part of this partnership but really what we're all trying to do is be on the same page in terms of figuring out what exactly our priorities are, making this program actually work. Helping, working with each other to try to communicate with the public to tell them exactly what we're trying to do and what our expectations are, how things are working. And of course you have the provincial people that help with the regulations and to help with a lot of the monitoring, industry is a part of that as well.  You just have a lot of different experts from all different levels of government and the private and public sector that are that are trying to make this program work.

- Joël Houle
I'm sure many people will remember the last spruce budworm outbreak in the 70s and 80s. I think there were 50 million hectares of forest that were damaged. How does the public respond to the early intervention strategies? Is there much support?

- Rob Johns
Yeah. There's so far there's has been considerable support for it. I mean I give quite a few talks for spruce budworm and there is very rarely that I've given a talk where there's not somebody that can have memories of the previous spruce budworm outbreak. They might have been young at the time, they might have owned a wood lot, they might have had parents that were working in the forest industry or attended parks that were being defoliated by spruce budworm. Everybody has a story about the spruce budworm from the old times. And of course there was there was some controversy around the management bill and during those times.  And so of course a lot of those concerns have carried over into the current outbreak. There is almost a 25-year gap from the previous budworm outbreak to the current one. So there's a lot of long memories for not just the defoliation but some of the controversy around insecticide treatments as well. So a big part of the program I would say even probably one of the most important parts of the program is actually trying to explain to the public what we are trying to do, how things have changed, you know a lot of the old insecticides we used to use have all been banned. And we use new fairly much less invasive types of insecticide like BTK and tebufenozide . And so a big part of this is actually trying to explain to the public exactly what these are, explain how the program actually works, emphasize the point that we're not trying to wipe out spruce budworm by any means but we're actually trying to add a little bit of mortality to those populations so they're a little bit lower. And so that natural enemies and other natural factors can keep those populations at bay. And so a big part of our role and this is this is you know one of the main mandates of this healthy forest partnership as well is to explain to the public how all of these pieces work. And at the same time of course this is an ongoing experiment determining whether the program actually works. Now if we can show that the program actually works and we can explain both the costs and the benefits of this program, it's ultimately up to the public to make a decision whether or not they're going to actually use this on the forest. And so that's why communication is such an important part of that.

- Joël Houle
So you're now in year six of this research right? How are the results so far?

- Rob Johns
We started in 2014. And a lot of this is centered on northern New Brunswick in eastern Canada where the outbreak was just starting to encroach on the border coming from the north in Quebec and so populations were still relatively low then but it didn't take very long for them to, it was about over about three years they increased to cover at least our treatment areas covered up to almost 220,000 hectares as of 2017. So it had expanded very very quickly which is pretty characteristic of a spruce budworm outbreak. This past year saw almost a 90 percent decline in the number of hot spots or these areas that we were protecting from the previous year. And in our evidence so far seems is just it was partly associated with sort of this natural enemy complex and natural conditions pulling the populations down. But also I think it's pretty clear that we are having an impact on these populations as well through this program of early intervention strategy.

- Joël Houle
What's next for the early intervention strategy?

- Rob Johns
So right now, as I mentioned we had 220,000 hectares from last year that were treated. This year the population has declined so much in New Brunswick that we have just 10,000 hectares to treat, you know a huge decline. And so we have a very large area where we had been working in past years and controlling the populations and there's not much for populations there. So the question now is how do these populations sort of rebound or if they rebound at all? And so I mean I'm a population ecologist and so I'm interested in understanding what factors actually contribute to these populations rising.  Do they get inundation from moths coming from Quebec or is it a sort of local intrinsic forces that cause these populations to rise by themselves and trying to actually get an understanding of how sustained the impacts of this early intervention approach are for the area.

- Joël Houle
If our listeners would like to find out more information on either spruce budworm or the early intervention strategy are there any resources available online that you would like to direct them to?

- Rob Johns
Yes. So if there is we have a very comprehensive website. It is just being refreshed for this upcoming year I think it's going to be active within the next month or so. The website is www.healthyforestpartnership.ca. I would also like to draw attention to a citizen science program that we've had in operations for the last four years, it's our budworm tracker program. And this is a program whereby the general public from throughout eastern Canada can send us an email and we will send them a trap for collecting spruce budworm moths. Everything's free of charge and this is one of the ways through which we monitor spruce budworm, and I should say it's also part of our communication strategy for engaging with the public. To sort of talk about spruce budworm issues as well. So either of those you can go to the website and you can get information. We also do a little bit of blogging on there or you can check out our citizen science program, budworm tracker, we have a Facebook page as well. And we're always happy to talk to people and if people have questions and they reach out to the website you very well might get a question or an answer from myself or one of the other scientists working on the program.

- Joël Houle
Sounds good. We'll put the links to those those resources into our podcast description. Thank you so much Rob for your time today.

- Rob Johns
My pleasure.

- Joël Houle
So this is the end of the episode but like always it doesn't mean it's the end of our conversation. If you have any follow up questions for our experts get on Twitter and tweet at us using the hashtag "#AskNRCan". Also if you're interested in learning more about the scientific work that we do at Natural Resources Canada check out our online magazine called simply science. We have a ton of great content for you including articles videos and previous episodes of this podcast. If you check out the podcast page for this episode we'll have links available to any relevant material so you can learn more about what we talked about today.  The best way to find simply science is either to google it or click on the banner from our Web site at NRCan.gc.ca. And if you'll like this episode and you're listening to us on Apple podcast, Google Play, Stitcher or SoundCloud please leave a review and subscribe so you can check out any previous or future episodes. That's it for us today. Thank you for listening. We look forward to hearing from you and we'll see you next time.