PARENT SESSION
Poster Session #3: Invertebrate Ecology.
Monday, August 5. Presentation from 5:00 PM to 6:30 PM. Exhibit Hall B & C, TCC

Competition and host selection for oviposition sites by Monochamus scutellatus (Say) and other phloem feeding beetles.

Lazarus, Laura^*,1, McCullough, Deborah^1,2, ¹ Michigan State University, East Lansing, MI² Michigan State University, East Lansing, MI

ABSTRACT- Monochamus scutellatus (Say), the white-spotted pine sawyer, is an economically and ecologically important native insect in Northern conifer forests, but information regarding host preference is sparse. We evaluated the host preference of adult M. scutellatus and interspecific competition for phloem with scolytids in one stand each of red pine, white pine, jack pine and Norway spruce. Eight trees of white, red, jack pine and white spruce were felled and cut into 38 cm bolts. Bolts from two trees of each species were placed end to end in each stand in a completely randomized block design. We observed M. scutellatus adult activity and behavior, and recorded the number of predators and other phloem feeders on each bolt from May-August. All four conifer species were suitable hosts for oviposition by M. scutellatus. Females oviposited on the sides of bolts more often than other areas, suggesting the importance of suitable microclimates for developing larvae. To assess phloem competition, we dissected one-third of the bolts. Gallery length and phloem consumption were determined for M. scutellatus, curculionids, and scolytids, and gallery interceptions were recorded on each bolt. Area of phloem consumed by M. scutellatus and number of gallery interceptions of phloem feeding species on each bolt did not significantly differ among conifer species.

KEY WORDS: interspecific competition, Cerambycidae, host selection, Scolytidae