Forest tent caterpillar: 2013 update

Look for potential population increases in northern and northeastern counties and a continuation of the FTC population in western and west-central counties.

Potential Forest tent caterpillars activity for 2013

During the 2012 summer aerial detection survey, 274,000 acres of defoliation were mapped. Looking at the acres defoliated by FTC in 1885–2012, these populations could be building toward a 2014 or 2015 peak.

Acres defoliated by foreset tent caterpillars, 1985 to 2012

Highlights from 2012 aerial detection survey

  • From Beltrami and Lake of the Woods counties to Cook County, aerial survey was delayed by two months and very few acres with FTC were mapped, so we really don't know how extensive FTC populations were. We'll have to wait until the summer of 2013 to fill in this gap.
  • A dozen 60-acre pockets of defoliation were mapped in Fillmore and Houston counties, which is a rare occurrence.
  • Far from declining, the FTC populations in west-central counties are going strong. Basswood and oaks are the primary targets there, and both species might be in trouble of declining in 2013 due to the duration of local outbreaks.