Red Belted Clearwing Moth - What’s All the Buzz About?

Many apple growers who have had pheromone traps placed in their orchards by the Canadian Food Inspection Agency (CFIA) are wondering what is going on. Last year the apple clearwing moth (Synanthedon myopaeformis), also known as the small red-belted clearwing moth, was found for the first time in North America in British Columbia. The apple clearwing moth is a pest of apple, pear, crabapple, quince, plums, apricots, cherries, hawthorn and mountain ash in Europe. The CFIA is conducting a national survey in all fruit growing regions in Canada in 2006.

The larvae tunnel under the bark in the tree trunk causing irregular feeding galleries. They prefer burr knots, especially on M 9 rootstock, and infestations in Europe have been associated with the European canker caused by Nectria galligena. Similar to dogwood borer, larval feeding shortens the life of trees and may lead to considerable yield loss. There is only one generation of this insect each year. Unfortunately adult emergence lasts from May through September, and as a result insecticide sprays aimed at managing dogwood borer may not provide subsequent control of the apple clearwing moth.

The CFIA is using peach tree borer pheromone traps to monitor for the adult clearwing moth. Adults have a 20-25 mm wingspan, with a dark blue-black body and a bright red band across the abdomen, behind the base of the transparent wings. The larvae are 15-20 mm in length and white with reddish-brown head.

The CFIA is monitoring more than 50 orchards in Ontario to determine if this insect is present. Currently they have not announced the results of their 2006 survey. Should the apple clearwing moth be found here in Ontario, many of the cultural controls already used for managing dogwood borers (i.e. painting the trees white to deter oviposition, managing weeds near tree trunks, and avoiding the use of mouseguards that encourage egg laying) would help to manage this pest. Since this is a new pest to North America, there are no pesticides registered yet in Canada for the control of apple clearwing moth. Research trials are being conducted in British Columbia using Isomate-P mating disruption. Preliminary results are expected at the end of the season. For more information on the apple clearwing moth refer to the British Columbia Ministry of Agriculture and Lands website.

Related Links:

• British Columbia Ministry of Agriculture and Lands - apple clearwing moth