| Conservation plantings of native wildflowers were established alongside blueberry fields to test the hypothesis that provision of resources for natural enemies and bees increases their abundance in adjacent crop fields. For two growing seasons (2007 and 2008), at four commercial blueberry farms, fields with flowering field borders were compared to control fields where growers maintained field borders of mown grass. In both years, this revealed contrasting effects of the presence of flowering plants on representative groups of natural enemies, pests, and pollinators. Natural enemies, wild bees, and some pests were consistently more abundant in fields adjacent to flower plantings. A laboratory evaluation was also performed to compare the longevity of three different commercially available natural enemies: a lady beetle (Coleoptera: Coccinelidae: Hippodamia convergens Guerin-Meneville), a predatory bug (Heteroptera: Anthocoridae: Orius insidiosus (Say)), and a generalist aphid parasitoid (Hymenoptera: Braconidae: Aphidius colemani Viereck), caged with cut flowers from the border plantings. Natural enemies exhibited a variable pattern of sensitivity to provision of flowers, with A. colemani being the most sensitive, O. insidiosus intermediate, and H. convergens being relatively insensitive to flower availability. |
