I went to a panel discussion in Kanata on March 27, 2013, to discuss the Ottawa’s approach to the EAB problem. Ash trees are dying at a paralysing rate; the pest has already killed 50 to 100 million trees in North America since EAB was discovered in the Detroit-Windsor area in 2002. From that point, EAB has been spreading in all directions, infesting 65,000 hectares in Ontario and recently hitting Quebec and 17 states. In the United States, three types of parasitic wasps were imported from Asia (one species attacks the larvae and the other two attack the eggs). It hasn’t yet been determined if their numbers will increase to the point of an effective controlling measure, but all three species successfully over wintered. The Canadian Forest Service and Ministry of Natural Resources are considering following suit to release wasps in Canada. In Canada, the Canadian Food Inspection Agency is in charge of biological control measures, but (as expected) processes are very slow going and it is part of a long-term plan. The beetle was discovered in 2008 in Ottawa, and the city council has banded together to form a management program. The Council’s EAB strategy consists of five steps:
1. Regulation of wood movement/disposal
2. Tree removal
3. Selective tree injection
4. Proactive tree planting
5. Public awareness and outreach
IDENTIFICATION: The emerald ash is a metallic green wood-boring beetle (1/2” long 1/8” wide) native to China and Eastern Asia; the larvae are white and flat and can grow up to 1”. The beetle attacks all North American true ash trees (of the genus Fraxinus); it does not invade other tree species. The beetle lays eggs beneath the bark and feeds on the leaves; the larvae feed on the wood beneath the bark leaving “s” shaped galleries. Upon infestation, the tree’s ability to transport/nutrients is choked and the tree starves.
How to identify an infected tree:
dieback at the crown and loss of green in leaves at the top of tree
fewer and smaller leaves
epicormic sprouts (they look like small shoots/suckers in the lower regions of the tree)
Because the bug is hidden beneath the bark, infested wood is often moved without people knowing and this ultimately spreads the pest. Please don’t move firewood or anything you suspect is ash.
Bioforest Technologies Inc are the only government-endorsed injection provider. The product is called TreeAzin. It is a biologically based insecticide made from the oil of neem trees and it’s required biannually. The injection method is fairly invasive because you must drill multiple holes at the base of the tree to administer pesticide, and it is a short-term plan until scientist develop an effective response. The pesticide, after it is injection, is transported through the vascular system and into the leaves; it targets female beetle adults eating the leaves, and sterilizes the female. The pesticide also disrupts normal molting in the larvae and kills the larvae this way. Injections are a preventative technique; if the tree can’t transport nutrients due to the activity of the beetle, it isn’t effective as the insecticide cannot be transported throughout the tree after injection. Planting suitable replacement species is a very good proactive measure if you have many ash trees on your property. After infestation, the ash tree is expected to live between 2-5 years; that is a pretty good chunk of time for a new tree to grow.
Public awareness is the best advocacy step. People should know how to identify an ash tree (especially so it isn’t accidentally moved), know that the trees are at risk, and think about the best steps to manage existing ash trees. Part two of the discussion will follow my conversations with local authorities, as provincial and municipal efforts vary depending on areas. I hope to lay out the ash management plan for the Gatineau Hills area, but in the meantime residents should consider taking a walk on their property to see if they can spot an ash tree. Here is a tree identification guide to help you out:
http://treedoctor.anr.msu.edu/ash/ashtree_id.html