Evaluation of Insecticides for Control of Overwintering Hylurgopinus rufipes (Coleoptera: Curculionidae)

Abstract

A bark disk bioassay was used to assess the effectiveness of different insecticides for control of overwintering adult native elm bark beetles, Hylurgopinus rufipes (Eichoff) (Coleoptera: Curculionidae). Insecticides were applied to the base of the trunks of living American elm trees, Ulmus americana L., and bark disk samples were removed at intervals with a hole saw. Adult H. rufipes were exposed in bioassay chambers for which the bark disks formed the floor of the chamber. In September 2005, chlorpyrifos, permethrin, and a water control were applied to trees in five replicated blocks, and bark disk samples were taken at intervals over the following 725 d. In September 2006, chlorpyrifos, permethrin, carbaryl, bifenthrin, and a water control were applied to trees in six replicated blocks, and disk samples were removed at intervals up to 1,163 d after application. In both experiments, beetle mortality was 100% on chlorpyrifos-treated disks removed up to 725 d after treatment and, in the 2006 trial, declined thereafter. The pattern of mortality in the bifenthrin treatment did not differ significantly from that in the chlorpyrifos treatment in the 2006 experiment. Average corrected mortality on disks treated with permethrin or carbaryl declined below 100% by 11 d after application. On disks removed in the May following treatment, 248 d after application, average corrected mortality was 42-44% on permethrin-treated disks and 26% on carbaryl-treated disks.

Bionomics ofScolytus schevyrewi(Coleoptera: Curculionidae) in Saskatchewan and Manitoba, Canada

“…Unlike most other areas of North America, where the disease is responsible for the loss of most U. americana trees (Brasier 2000), the species continues to be an important shade tree in urban areas in Manitoba and Saskatchewan, and there are ongoing integrated Dutch elm disease management programmes to protect it (Westwood 1991;Domke 2005). A major component of these programmes is insecticide applications to the base of U. americana trunks to control H. rufipes which, on the prairies, overwinters only as an adult at the base of elm trees (Oghiakhe and Holliday 2011). The published information on the natural history of S. schevyrewi presents an overwintering behaviour that differs considerably (Yang et al 1988), and so changes may be necessary if the programmes are to remain effective.…”

Chemical control in forest pest management

“…Currently, chlorpyrifos, permethrin, and carbaryl are registered for control of elm bark beetles for application by basal spraying. Of these three, chlorpyrifos is the most effective against elm bark beetle (Oghiakhe and Holliday 2011). Booth and Johnson (2009) also reported good efficacy of acephate delivered by stem injection against red elm bark beetle, Magdalis armicollis Pierce (Coleoptera: Curculionidae), in elm.…”

Rapid Removal of Symptomatic Trees Reduces Dutch Elm Disease Infection Rates

“…In 2010, the program had a budget of CAD $1.3 million and operated in 31 urban communities and in buffer zones surrounding the Cities of Winnipeg and Brandon, both of which have their own management programs. Main elements of the programs are area-wide sanita-tion of diseased and declining elms, regular insecticide applications to the basal part of healthy elm trees to control overwintering H. rufipes (Jin et al 1996;Anderson and Holliday 2003;Oghiakhe and Holliday 2011), and regular pruning of dead wood.…”