NUMBER OF EGGS LAID BYTHE SPRUCE BARK BEETLE IPS TYPOGRAPHUS (L.) (COLEOPTERA: CURCULIONIDAE: SCOLYTINAE) ON TRAP TREES: INFLUENCE OF SELECTED FACTORS

Data for the spruce bark beetle Ips typographus (2942 measurements concerning number of eggs deposited per gallery, length of maternal galleries, and density of family galleries) were collected from 122 trap trees and 398 bark samples in three regions in 2008-2009. The mean maternal gallery was 78 mm long and the established mean egg-laying by one female was 35 eggs. The number of family galleries per m 2 of trunk ranged from 6 to 330 and was negatively correlated with the number of eggs deposited per gallery. The length of the maternal gallery was positively correlated with the number of deposited eggs. Because the number of family galleries per m(2) was not correlated with the length of the maternal galleries, the relationships were described by the following multidimensional linear regression: y = 15.45 + 0.29*x(1) - 0.02*x(2) , where ; gallery length, x(2) = number of family galleries per m(2) and y - number of eggs deposited per female.