Evaluating targeted aerial spraying for insect control

摘要

The main target zones in early plans for eradicating painted apple moth (PAM) (Teia anartoides) in Auckland, New Zealand, were narrow riparian strips of vegetation and steep gullies. However, there were concerns that achieving high levels of Bacillus thuringiensis var. kurstaki (Btk) deposition in these riparian areas, with minimal drift onto residential areas, would be difficult. This is because, with a combination of small droplets and high release heights, there would be considerable downwind movement of the spray cloud. The concept of targeting riparian strips was evaluated using an aerial spray application simulation model. Results indicated that targeted spraying is not a practical proposition, at least where small droplets are used and highrelease heights are required. The only solution would be to build larger target areas around the riparian strips. For targeted spraying to become a practical proposition, techniques must be developed for achieving efficacy using much larger spray drople