The oak leaf shredder, Croesia semipurpurana (Kearfott), has been a particularly persistent pest of red oak, Quercus rubra, in southern Ontario for several years. It is capable of completely defoliating mature trees leading either to increased susceptibility to disease or mortality. In 1980 about 800 ha in southern Ontario required spraying with Orthenem insecticide (Howse and McDowall 1980). The development of a sex pheromone lure for the oak leaf shredder would be valuable for survey purposes, post-insecticidal spray analysis of adult survival in treated plots, and for potential direct control by means of the disruption technique. Recently mixtures of (E)-11-tetradecenal (E11-14:AL) and Z11-14:AL in the ratios of 80:20 to 90:lO were found to be attractive to male moths (Weatherston et al. 1978). A local outbreak of oak leaf shredder in Sault Ste. Marie afforded an opportunity to determine the insect's response to modifications of the aldehyde blend in order to improve the efficiency of pheromone trapping of this species.

The methods of Foott and Boyce (1966) and De Ponti and Inggamer (1976) are inadequate to elucidate the residual toxicity of pyrethroids on predacious mites. These products irritate mites to such an extent that, shortly after their exposure to treated leaves, most if not all of the mites attempt to escape the irritant and in the process they are either caught in the Tanglefoot or drown in the water barrier.

Timing traps are widely used to study the diurnal flight activity of insects, their response rhythms to physical and chemical (olfactory) stimuli, and the effect of weather factors on these behaviors. Goetz (1941) used an adhesive-coated horizontal metal disk driven by a mechanical clock to determine the periodicity of male-female attraction in two lepidopterous species on grapes. The area of the disk exposed at any time corresponded to a 1-h sector of the clock dial. The disk completed a full revolution every 12 h and therefore the trap had to be checked twice a day. Also, since the clock speed was not variable, the trapping interval could only be adjusted by decreasing or increasing the opening to the sticky disk.

A study currently under way required non-attractant traps to collect and preserve for taxonomic identification flying insects inhabiting the crown and shrub layers of a slash pine (Pinus elliottii var. elliottii Engelm.) and pondcypress (Taxodium distichum var. nutans (Ait.) Sweet) forest. We concluded that an omnidirectional flight trap was appropriate. After failing to find a satisfactory design in the literature, we developed the trap illustrated in Fig. 1. Our design combines an original upper collecting unit with a modification of the trap described by Hines and Heikkenen (1977).

Larvae of the sawfly genus Gilpinia Benson, a Palaearctic genus, attack conifers. Smith (1974) listed 24 species, two of which, G. frutetorum (Fabricius) and G. hercyniae (Hartig), were accidentally introduced into North America. Keys to known species of Gilpinia have been published for adults (Enslin 1917; Takeuchi 1940; Gussakovskij 1947; Berland 1947; Benson 1951; Okutani 1958) and for most European larvae (Lorenz and Kraus 1957; Běnes and Kristek 1979).

The author (1977) reported on 10 species of insect parasites that were reared from field-collected larvae or pupae of the darksided cutworm, Euxoa messoria (Harris), in Ontario. Of those, eight species had not been previously recorded from this host. During subsequent studies at Delhi, Ontario in 1976 and 1977, more than 3000 larvae of this cutworm were collected from rye and tobacco fields and reared in the laboratory, using methods previously described (Cheng 1977). From this work four more species of primary endoparasites were newly recorded, namely, Apanteles laeviceps Ashmead (Braconidae), Apanteles militaris Walsh (Braconidae), Campoletis sp. (Ichneumonidae), and Meteorus communis (Cresson) (Braconidae). Arenetra sp. reported in the earlier work appeared again and was determined to be A. rufipes vernalis Walley (Ichneumonidae).

The egg parasite Ooencyrtus ennomophagus Yoshimoto (1975) is a good candidate for the biological control of certain defoliators. In 3 years it eliminated an outbreak of the elm spanworm, Ennomos subsignarius (Hübner), that reached from southeastern New York State across Connecticut and into Rhode Island (Kaya and Anderson 1974). Timely biological control, however, requires maintenance of parasite cultures in a laboratory for mass production when the need arises. Adults of O. ennomophagus live for about 3 months in the laboratory, but supplying them with suitable host material has been a problem. Drooz and Solomon (1980) found that the eggs of the factitious host, the notodontid Clostera inclusa (Hübner), could be stored at −10°C for a month and used for culturing O. ennomophagus. Tests under way indicate that the eggs may be stored longer than 12 months. I report here the development of O. ennomophagus in eggs kept at −10°C but not in fresh eggs of the pine looper, Lambdina pellucidaria (Grote and Robinson). The results indicate a potential for rearing parasites on treated eggs of non-host insects, if the need arises.