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The mountain pine beetle epidemic that is spreading eastward through Jasper National Park is expected to only get worse after an unseasonably warm winter, according to Dave Smith, a fire and vegetation specialist with Parks Canada.

Since January 11, he said there have been only eight days where temperatures remained below zero throughout the entire day allowing the beetle to survive the winter relatively unscathed.

鈥淚f we continue to get the warm winters that we鈥檙e getting I think there鈥檚 a good chance that we鈥檙e going to see the beetle do really, really well,鈥� said Smith, during a public information night, May 18.

In March, Parks Canada reported the beetle colonized just over 21,500 hectares of the park鈥檚 pine forests, more than three times the amount mapped in 2014. A year earlier the agency mapped 122 hectares.

In March the agency also released details of its draft mountain pine beetle strategy, which Smith said would be published 鈥渟oon.鈥�

The draft strategy lays out three main tactics the park intends to use which includes cutting down and burning individual trees colonized by the beetle, using prescribed burns and using machinery to widen fireguards around the townsite.

鈥淭he most important thing is identifying trees,鈥� Smith told the audience.

鈥淚f you identify beetle trees and you let us know we can take them down.鈥�

He said the easiest way to identify whether a tree has been colonized or not is to look for pitch tubes, or globs of sap on the outside of the tree where the beetle began tunneling.

To help residents in town, the municipality in conjunction with Parks Canada has also begun giving away free verbenone pouches people can attach to their trees to stop the beetle from attacking healthy trees.

Verbenone is a pheromone naturally produced by adult beetles to let other beetles know a tree has already been colonized. The idea is that if people attach a pouch of artificial verbenone to a tree it will tell other beetles to stay away, thereby protecting it.

The pouches should be placed on the tree as high as possible by mid-June and are safe around humans and pets.

鈥淭hey鈥檙e about 80 per cent effective if used properly,鈥� said Smith. 鈥淚t鈥檚 really worth doing.鈥�

The mountain pine beetle kills pine trees by burrowing under the bark and mining the phloem, the layer between the bark and wood of the tree. The beetles then lay eggs under the bark. After the eggs hatch, the grub-like larvae spend the winter feeding under the bark. The larvae pupate in the spring and usually emerge as adults from June 15 to July 1 before moving onto the next mature pine tree.

In addition to the damage caused by the beetle, which has a one-year life cycle, the species transmits a blue stain fungus during colonization. The combination of beetle tunneling and blue stain fungi disrupts the movement of water within the tree rapidly killing it and turning it red and dead.

The successful reproduction of the mountain pine beetle depends on several factors, including daily temperature fluctuations, under-bark temperatures and the 鈥榳inter-readiness鈥� of beetle larvae.

According to the province, the temperature at which beetles start to die is not fixed, but varies given the larvae鈥檚 response to daily temperature fluctuations.

For example, an under-bark temperature of 鈥�37 C will kill 50 per cent of a mountain pine beetle population, however, a temperature of 鈥�20 C in the fall, before the beetles are prepared for winter, or in the spring, when beetles are starting to become more active, will also kill beetles if it is preceded by temperatures above 0 C.

鈥淏ased on what we鈥檝e seen both from weather and from me poking around in the woods I think there鈥檚 a really, really high survivorship,鈥� said Smith, explaining he should have a better understanding about how well the beetle did this winter in the next few weeks.

鈥淚 am very sad to say that I think that they did incredibly well this year, better than ever.鈥�

The other reason the beetle appears to be doing so well is because the park鈥檚 forests are becoming older making the trees more susceptible to the beetle.

鈥淥ur fire history shows us that we had fire in the montane valley every five to 50 years and in the lower subalpine every 90 years,鈥� said Smith.

Due to decades upon decades of fire suppression, trees have grown to an age that makes them a prime target for the beetle.

鈥淏eetles are most effective after the trees are 60 plus years old,鈥� said Smith, 鈥淲e haven鈥檛 had a big fire in this valley for over 100 years so we have a lot of trees that are over 60 years old.鈥�

Part of the reason the pine beetle is such a large problem is because dead trees increase the fire danger in the park.

鈥淲e have one of the best fire smart programs in all of Canada. There鈥檚 not many towns our size that can boast 1,000 hectares of fire smarting,鈥� said Smith.

Despite this, he said Parks intends to carry out a series of small prescribed fires this summer just west of town and over the next couple of years strengthen several fire lines around town.

For more information about the verbenone pouches contact Janet Cooper, the environmental stewardship coordinator at 780-852-1563 or email [email protected].

Paul Clarke
[email protected]

Using verbenone to protect trees from the mountain pine beetle

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About verbenone:

• Artificial verbenone pouches can be used as a short-term treatment to protect individual pine trees or stands from a mountain pine beetle attack.
• The beetle natural produces verbenone as pheromone to tell other adult beetles to stay because the tree is already colonized.
• Slow-release verbenone pouches are most effective in areas where less than 15 to 20 per cent of the stand is currently infested.

• Place the verbenone pouch as high as you can reach.
• For large trees place two pouches and stagger the height.
• Don鈥檛 puncture the verbenone pouch membrane.
• Staple or nail to the north side of the tree through the thin plastic strip that extends beyond the pouch, not through the thick part of the pouch.
• Placing the pouch on the north side prevents sunlight from warming the pouch and depleting the verbenone prematurely.

• The pouch should be in place by mid-June.
• Beetle flight is usually between June 15 and July 1 for most species.
• The verbenone pouches are only effective for one season.

• Keep trees healthy by watering them well. A healthy tree needs to be well hydrated to produce pitch and sap. The tree oozes pitch when attacked as a defense mechanism against the beetles.
• Don鈥檛 prune or trim the pine tree. The beetle looks for injured, diseased or unhealthy trees and when cut the tree emits a compound that signals distress that beetles pick up on.
• Be sure the verbenone pouch is being place on a pine tree not a fire tree.