Eastern Tent Caterpillars Up in 2016

Kentucky’s eastern tent caterpillar population has been growing steadily over the past few years. However, the trend appears to have accelerated; tents and defoliated cherry trees were very noticeable this spring (Figure 1).

Figure 1. Small wild cherries defoliated by eastern tent caterpillars. (Photo: Lee Townsend, UK)

Figure 1. Small wild cherries defoliated by eastern tent caterpillars. (Photo: Lee Townsend, UK)

Many of the hairy caterpillars have left their nests (Figure 2) in search of pupation sites. Adults will emerge in early June and females will lay egg masses for the 2017 contingent, which may be even larger. With somewhere between 140 and 300 eggs per mass, a relatively small increase in the number of females can generate a big jump in numbers for the following season.

Figure 2. Tent caterpillars have abandoned this nest and entered their wandering stage. (Photo: Lee Townsend, UK)

Figure 2. Tent caterpillars have abandoned this nest and entered their wandering stage. (Photo: Lee Townsend, UK)

The normal cycle of these insects is a long, slow buildup, followed by 2 to 3 peak years before the population crashes from a combination of natural enemies and diseases. It would be wise to anticipate at least one more season before a crash. It is a good time to identify “hot spots” and a plan to deal with them. Tree removal may be a practical option along pasture fence lines.

 

By Lee Townsend, Extension Entomologist

Posted in Forest Trees, Landscape Trees & Shrubs