Photo by Monica Errico, USDA (taken on August 17th, 2011) CC-by-2.0
An article in the Toronto Star prompted me to write about the Asian longhorned beetle (Anoplophora glabripennis). It's an invasive species thought to have been introduced to North America from China and/or the Korean Peninsula on solid wood packaging materials (such as crates and pallets) in 1996.
The Canadian Food Inspection Agency (CFIA) and the Canada Border Services Agency has (thankfully) intercepted this pest numerous times since 1982. Yet it last appeared in the Greater Toronto Area (GTA) in 2013. A 2011 study concluded that an infestation could cause a loss in the ballpark of $702 million dollars.
In the U.S., it's estimated that nearly one-third of all trees would have to be destroyed if the Asian longhorned beetle were to spread.
When I researched this insect further I discovered just how difficult it is to keep at bay. The Asian longhorned beetle targets healthy and unhealthy trees – it's considered one of the world's worst invasive species.
U.S. Department of Agriculture (usdagov on flickr) CC-by-2.0Both North American and Europe have been affected by infestations.
Here in Canada, the trees most targeted have been birch, elm, maple, poplar, and willow.
And here's the kicker: the Asian longhorned beetle has no natural enemies in Canada.
As you can imagine, our forests and trees are home to countless species that are important to our ecosystems, our earth, and the air we breathe. Not to mention numerous forestry-related industries (especially maple syrup).
"Thunder" is the Asian Longhorned Beetle (ALB) Detector Dog shown as my banner photo. It was taken by Monica Errico of the USDA. Dogs are trained to recognize"frass" or excrement that the beetle leaves behind.
Drastic Measures to Eradicate the Asian Longhorned Beetle
R. Anson Eaglin (usdagov on flickr) CC-by-2.0I was shocked to learn just how much is involved to eradicate this beetle.
For example, a quarantine zone of about 150 km2 was established around the infested trees in Canada to restrict the movement of wood (and wood products) out of the area.
Even after 531 infested trees were destroyed, another 12,500 trees considered at high risk of being infested had to be destroyed.
In the U.S., the numbers are even more alarming. In New Jersey, an infestation of over 700 trees led to the removal and destruction of almost 23,000 trees.
So, I wondered what kills these beetles and do we need to resort to chemicals or are there any natural enemies of the Asian longhorned beetle?
Report From the Midwest Biological Control News
In a featured article titled The Potential For Biological Control of Asian Longhorned Beetle in the U.S., I discovered the following:
- The Asian longhorned beetle has the potential to infest and kill many deciduous forest trees in the eastern U.S., especially maple and sugar maple trees.
- If the spread of these beetles went unchecked, the USDA predicts they would cause a loss of $138 billion dollars annually to the U.S. economy.
- The only widely used method to stop the damage caused by the Asian longhorned beetle is the identification and removal of infested trees.
Are There Any Natural Enemies of the Asian Longhorned Beetle?
Actually, yes. They include other beetles, flies, carpenter ants, wasps, birds, lizards, spiders, scorpions, toads, small mammals, nematodes (worms) and fungi.
Yet the most promising natural predator is the cylindrical bark beetle (Dastarcus longulus). It can kill 60 percent of Asian longhorned beetles. In regions where the cylindrical bark beetle is found (in relatively high numbers), the Asian longhorned beetle is thought to be "under natural control." And this natural enemy (native to China) is currently under investigation for future use in the U.S.
But I always wonder if introducing another non-native insect is wise. It could wreak havoc with other species of plant, trees, insects, or other creatures. And when I searched for information about the cylindrical bark beetle, very little is known about them. Most consume fungi – but others are carnivores that feed on bark beetles and small arthropods.
ALB Damage Caused by Tunneling and Exiting Cut Trees
It's Important to Not Move Infected Firewood or Felled Trees
Watching Out for Asian Longhorned Beetles is Crucial
Since the Asian longhorned beetle spends 90 percent of its life within trees, it's extremely difficult to detect. During the short duration that it spends outside, it usually is confined to the middle and top canopy of trees. It also can survive a long time and infested cargo or firewood appear to be one of the key ways this beetle is spread.
The integration of methods resulting from the identification of weak links in the life history and behavior of Asian longhorned beetles (ALB) will play a major role in any management program.
This may include the use of detection methods, as well as direct control methods (i.e. insecticides, bait trees).
In conclusion, any one of these components, if exclusively utilized for management of ALB, will run the risk of jeopardizing any management program. Therefore, the integration of these methods will be essential for the management of ALB in the U.S.
In August, ALB Hatches and Emerges From Trees
And It Creates a Dime-Shaped, Round Hole in the Tree
The Most Comprehensive Website Devoted to ALB
In short, Asian longhorned beetles are more active this time of the year (August) so they are easier to spot. You may also see signs of them on the trees in your neighborhood as well.
You can report the beetle or the signs of damage online or by phone (1-866-702-9938).
Up next is a succinct, 31-second YouTube video which was published May 23rd, 2013. Because "once the Asian longhorned beetle infests a tree, there is no cure."