First spotted in Windsor in the summer of 2002, the EAB attacks and kills most species of Ash (Fraxinus sp.). Ash is an extremely important genus in Canada and the economic and ecological impact of this pest is significant – the City of Windsor is currently removing between 6,000 to 9,000 dead or infested street trees. A tree plantation in Essex County was quarantined after its 70,000 Fraxinus, destined for hockey sticks and baseball bats, was found to be infested. Ash trees are an important component of forests in eastern Canada and the U.S., and are extensively planted as urban and shelter belt trees throughout Canada. EAB was first reported in spring 2002 across the border in the U.S. and is under active eradication at several sites in Michigan, and one site in Lucas County, Ohio.
Movement of firewood and Fraxinus nursery stock regulated
All logs, trees, wood with bark attached, wood chips or bark chips and nursery stock of Fraxinus, as well as firewood of all tree species is restricted from movement outside the regulated areas of Essex County. Marchant reports the movement of firewood has been a significant pathway for EAB, and is responsible for infestation of nursery stock of at least one nursery in Michigan.
CFIA distributed information packages to municipalities, conservation areas and campgrounds across the province to alert them to the significance of EAB. It also conducted a mass mailing to residents in Essex County, advising them of the restrictions and dangers of the movement of firewood. Marchant asks the nursery and landscape industry to be particularly careful when moving ash trees. The U.S. is looking for assurance that ash nursery stock is free of EAB, and CFIA inspectors will verify that trees presented for export do not originate in infested or regulated areas of Canada or the U.S. He advises that ash exports could be held up at the border. CFIA staff will also monitor ash in nurseries across Ontario to ensure they remain EAB-free.
The EAB is difficult to detect because adults are small (9 to 14 mm) and the larvae tunnel beneath the bark. Often, by the time deterioration is noted, it is too late to save the tree. Physical signs of EAB infestation include small “D”-shaped exit holes in the bark, vertical bark cracks over “S”-shaped larval galleries, basal sprouts or suckers on ash trees and dieback or deterioration of the crown.
There is no pesticide currently registered to control EAB. Currently, infested trees on the edge of infestation are removed and destroyed by CFIA by either chipping or burning to reduce the risk of spread to non-infested areas. Marchant reports scientists in the U.S. and Canada are working together to find an effective pesticide. “Despite active research being conducted, there is no quick fix or silver bullet on the horizon and it is unlikely any pest control products for EAB will be available in Canada before the end of 2004. Our best hope is an integrated pest management strategy that takes good advantage of any biological agents that may already be present here, coupled with good management strategies,” says Marchant.
Click here for more information on EAB.
View the CFIA directive outlining quarantine and phytosanitary requirements.
