- ペストロジー (ISSN:18803415)
- vol.23, no.1, pp.7-9, 2008-05-18
Seventy-two houses infested by dark-brown ants, Lasius japonicus Santschi, were surveyed from April 2005 to September 2006 in Sapporo and neighboring cities. The ants were active in the warmer seasons, especially in June. The infested houses were categorized into two types: less than 5 years (30.6%) or more than 21 years (27.8%) after construction. These phenomena might be caused by changes in the external insulation in recent houses and the house deterioration in aged mortared houses.