Flight and Dispersal of the White-Pine Weevil1

Abstract

flight and dispersal of the white-pine weevil, Pissodes strobi (Peck), through a white pine plantation was studied by releasing 409 marked weevils at a central point within a 1431-tree plantation and checking every tree at 5-day intervals. Weevils flew readily at the time of release. Marked weevils were recorded throughout the plantation, up to 330 feet from the release point. A few weevils were observed on the scattered white pines 200-300 yards from the release point beyond a hardwood barrier. Total numbers of weevils present on leaders increased from April 25 to May 4, after which the number steadily decreased. Males were slightly more abundant on leaders early in the season and females were slightly more abundant later in the season, but there were no sex-related differences in dispersal. A concentration of weevils within 30 feet of the release point was attributed to short-range flight with the wind direction. Taller trees and longer and thicker leaders were related to higher percentages of tree visitation by weevils.