a1 Research Station, Agriculture Canada, Fredericton, New Brunswick
Gauze covers placed over the entrance of one air intake louver (1.52 m × 1.52 m, ht. 11.85 m, air passage 3055.8 cu.m/min) on the penthouse of the Research Station, from May until December, during a 3-year period, trapped more than 150 aphid species. In addition a considerable amount of intercepted aphid material was identified to genus only. A total of 31,482 specimens were trapped over the period.
Five species, Rhopalosiphum maidis (Fitch), Rhopalosiphum padi (Linnaeus), Mindarus abietinus Koch, Alhis craccae Linnaeus, and Capitophorus eleagni (del Guercio), predominated in all years. In 1967 and 1968 more than 100 specimens each of Pterocallis alnifoliae (Fitch), Tinocallis ulmifolii Monell, Myzocallis occultus Richards, Prociphilus americanus (Walker), Capitophorus hippophaes (Walker), Hayhurstia atriplicis (Linnaeus), Thuleaphis rumexicolens (Patch), and Myzus persicae (Sulzer) were trapped each year.
Once potential development temperatures were reached there was little correlation between mean temperatures and aphid numbers up until frost.
The earliest interception was 6 May; general dispersal was under way by 6 June and continued until late November, despite preceding October frost.
(Received October 06 1975)