• Miller, C.A.
  Canadian Forestry Service
  
• Kettela, E.G.
  Canadian Forestry Service
  

In a recent report (Miller et al. 1971), we outlined a method of extracting and counting overwintering larvae of the spruce budworm (Choristoneura fumiferana (Clem.)) from sample branches at minimum cost. The essence of the technique was to wash the branches in a warm sodium hydroxide solution that dissolved the hibernaculum webbing and freed the larvae. Since publication, we have field tested the technique by paired counts of overwintering second-instar larvae and feeding third-instar larvae in selected plots. In most instances, the counts were very similar indicating little or no spring dispersal loss. This was unexpected because earlier investigations (Miller 1958) revealed that spring dispersal losses up to 71% were not uncommon. In this report, we discuss these conflicting results and reevaluate the washing technique.