Masses of forest tent caterpillars have emerged in some city neighbourhoods to do what forest tent caterpillars do – eat the leaves of various deciduous tree species including poplar, aspen, birch and apple.Taylor Scarr, director of the integrated pest management division at the Great Lakes Forestry Centre in Sault Ste. Marie, travelled to Thunder Bay last week and said he noticed "a fair bit of forest tent caterpillar defoliation" on aspen stands in the area.
"Although it's unsightly and the insect is a nuisance, it will collapse on its own and most trees survive," Scarr told TBnewswatch. Health Canada states that outbreaks don't happen on a precise schedule because they depend on several environmental and biological factors.Larvae begin to emerge in the spring, after passing the winter fully-formed within the eggs.
The tan-coloured moths are nocturnal and live for five to 10 days, during which they deposit eggs in grey, cylinder-shaped masses completely surrounding small twigs.In the summer, look for tough, yellow-to-white cocoons on tree trunks, fences, debris, and sheltered areas. In the fall, look for shiny, dark brown or grey saddle-like cases which straddle or encase twigs of trees that are known to be susceptible to tent caterpillar infestations.