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The comparative abundance of orchard pest leafroller larvae was determined on eight host plants in the vicinity of pipfruit orchards. The greatest numbers occurred in Canterbury, followed by Nelson, Hawke's Bay, and Central Otago. In Hawke's Bay, leafroller larvae were Ctenopseustis H9800Q obliquana (41%), Planotortrix octo (15%), Epiphyas postvittana (16%), and Cnephasia jactatana (9%), and were most abundant on poplar, willow, and alder. In Nelson, leafrollers were E. postvittana (25%), Planotortrix excessana (23%), C. obliquana (23%), and C. herana (22%), found on willow, alder, clover, poplar, gorse, broom, dock, and plantain. In Canterbury, larvae were C. herana (51%), E. postvittana (34%), and P. octo (15%), mainly on broom, gorse, alder, poplar, dock, and clover. Leafrollers were very rare on host plants sampled in Central Otago, despite their pest status in horticulture. A total of 1460 larvae were reared to adults from the four regions, with 31% parasitism, of which two thirds were Dolichogenidea tasmanica (Braconidae). Parasitism varied significantly between leafroller larval host plants. Removal of leafroller host plants through mowing, pruning, careful shelter selection or other means could usefully reduce the leafroller pest density, and risk of incidence on crops.

Knowledge of host chemical volatiles has tremendously informed the fundamental understanding of plant-insect interactions as well as revealed opportunities for the creative use of plant-derived chemicals in the food and flavor industries and in insect pest management. This study was undertaken to assess the host searching behaviors of diamondback moth, Plutella xylostella L. (Lepidoptera: Plutellidae) females in relation to their mating status and conspecific larval herbivory. This involved measurement of odor-modulated upwind flight of female moths in a wind tunnel. Subsequently, the host location, recognition and acceptance behaviors of gravid females in relation to either intact uninfested or larvae-infested cabbage, Brassica oleracea L. (capitata group; Brassicales: Brassicaceae) hosts were compared in no-choice and dual-choice tests. Mating status had little effect on the female responses to host odor and flight duration. However, female moths were significantly more attracted to conspecific larvae-infested cabbage plants and had significantly shorter flights than in relation to intact uninfested cabbage hosts. Behavioral responses of gravid females were consistent when offered intact and larvae-infested cabbage hosts in both no-choice and choice tests in observation cages. Antennal rotation and ovipositor probing were found to be important in host searching and recognition, respectively, before a host was accepted for egg laying. Female moths oviposited significantly more eggs on larvae-infested cabbage than on intact uninfested cabbage and in particular more on leaves than on other parts of the cabbage plant. These results indicate the potential of developing a brassica host-derived kairomone attractant as a useful monitoring tool for female diamondback moths in area-wide integrated pest management programs that have a sterile insect technique (SIT) component.

European earwigs (Forficula auricularia L) were sampled in a Canterbury apple orchard over two growing seasons using shelter traps comprised of corrugated cardboard rolls Adult activity peaked during December and January in both seasons while activity of nymphs peaked two weeks earlier Earwig counts were consistently higher in a block receiving herbicide treatments compared with an adjacent block receiving pea straw mulch Competition between the sampling unit and the surrounding peastraw habitat probably explains this effect Factors affecting the sampling method used are discussed and the need for an alternative sampling system that better reflects absolute abundance is concluded