By Sarah Willis

THE BAD NEWS:
Asian longhorned beetle (ALHB), Anoplophora glabripennis, a non-native, large, wood-boring pest with a voracious appetite for a wide range of trees (maple, poplar, birch, willow, elm, ash and horsechestnut), has been found in parts of north Toronto and Vaughan.

THE GOOD NEWS:
ALHB is a ‘lazy’ pest and new adults tend to feed on the tree from which they emerged – if timely and effective controls are applied, it can be completely eradicated from the area.

Efforts to control and wipe out ALHB are being led by the Canadian Food Inspection Agency (CFIA), the federal body responsible for plant protection. CFIA is being aided in its efforts by staff with the City of Toronto and the City of Vaughan.

Since a member of the public spotted the first beetle in an industrial park on September 4, CFIA has amassed a substantial collective of expertise, including scientists across Canada and from cities in the U.S., that have successfully fought and eradicated recent ALHB infestations in Chicago and New York.

Ben Gasman with CFIA explains that while Canadians rely heavily on lessons learned by their U.S. counterparts, climate patterns and host tree species are different in Canada, so thorough surveys must be done to gather information about the pest before determining a course of attack. Richard Ubbens, City Forester for the City of Toronto, adds that in order to fight the beetle, we must first understand its dispersal patterns and population levels in Ontario. To this end, surveys are currently being conducted of trees on city-owned property in the 17,742-ha area currently identified as infested. (Maps depicting the infested areas of Toronto and Vaughan can be found on-line at www.inspection.gc.ca). It is assumed that several beetles came to the area in wood packaging from Asia four to six years ago. The ALHB infested primarily healthy trees for a number of years before building to significant population levels. “This is not just a Toronto problem,” Ubbens warns. “Everyone should look for signs of this pest – it could have come to a warehouse near you.”

All Toronto Forestry staff members have been trained to spot signs of ALHB infestation and neighbouring municipalities have sent staff to help CFIA, Toronto and Vaughan with ground surveying. Tree climbers have proven to be most effective at surveying for this pest, but ground resources are more readily available.

Gasman likens this stage of the ALHB fight to “the first chapter,” meaning there is a long journey of education, evaluation, understanding and action ahead. Surveys of city-owned trees within the identified area are nearly complete, with crews preparing to begin inspecting trees on private lands by mid-October. More detailed surveys of the infested ravine in Toronto are ongoing.

Along with a physical survey to delineate the extent of the problem, CFIA is working with partners in Toronto, Vaughan, the Canadian Nursery Landscape Association, Landscape Ontario and local conservation authorities to spread the word about ALHB and remind homeowners and contractors that no plant material is to be removed from the area roughly bordered by Hwy. 407, Hwy. 400, Finch Ave. W., and Milvan Dr. in Woodbridge and Toronto, as well as in the satellite infestations in the Ansley Grove Rd. area of Woodbridge, Beechwood Cemetery, and in the Thistletown area of Toronto.

Posters to aid in ALHB identification have been included with the November issue of Horticulture Review, and new hockey card-sized postcards are available from CFIA to help with field identification.

While it might seem like there is a lack of immediate action by various levels of government, it is important to understand the process of collecting complete information on this pest before beginning to remove trees. As Ubbens explains, valuable information can be gleaned from the infested trees. “By determining how old the exit holes are we can tell how fast the spread has occurred and map out the dispersal pattern.” He adds: “We need to plan our attack so it is efficient and effective. We want to go in to take out trees only once, so we have to get it right the first time.” On the other hand, Ubbens admits there is a need to start removing trees soon. “We have a lot of work to do before next June (when the adults emerge and begin flying again).” Taking down large, and in some cases apparently healthy, trees is another hurdle officials will soon have to cross. “Affected homeowners will have to first understand and acknowledge the severity of the (ALHB) problem and come to grips with the fact they will have to suffer the loss of their trees so others can survive,” Ubbens stresses.

CFIA says that the last thing they want to do is take down trees with active adults. Movement of the tree may trigger an unpredicted flight and spread the beetle further than usual, so it is prudent to wait until after a cold snap when the adults are dead before beginning to remove infested trees and adjoining host trees.

Apart from the surveying and removal efforts by arborists, there are actions that other sectors of the horticulture industry can take to ensure alien pests don’t decimate our urban forest again. Ubbens explains that tree replacement programs should focus on non-host species. “We need a palette of tree species to diversify the shade trees on streets of Ontario,” he says. “I realize there are many trees that are slow or difficult to grow or transplant, but growers need to start supplying a range of trees and native species.”

The burden of public education may fall to the retail sector, often on the front line selling shade trees to homeowners. “I challenge retailers to take the time to explain to their customers ‘this is more expensive, but you’re getting something different, underplanted or native,’” says Ubbens, admitting, “it takes time and money, but trees in our urban forest are the one thing in the landscape that will be around for decades. We should all invest more money and time in our trees. This is an instance where all of us working together, not just one sector alone, will make a difference.”

• Links to CFIA
  Click here for more info on EAB and ALHB.
• More CFIA links
  Update yourself on EAB and ALHB.
• Emerald ash borer and the City of Windsor
  The Canadian Food Inspection Agency (CFIA) continues to work to control the spread of the Emerald ash borer. Find out what action the City of Windsor has and will continue to take in eradication efforts.
• CFIA meeting focuses on EAB
  The results of the September 25th CFIA meeting on Emerald ash borer.
• OMAF speaks out on ALBH
  OMAF Nursery crop specialist Jen Llewellyn speaks up on the invasion of Asian longhorned beetle into the Ontario landscape.
• LO position on ALHB and EAB
  LO executive director Tony DiGiovanni calls for help in eradication efforts.