Abstract.1The potential for host plant‐mediated interactions between leaf‐chewers and the aphidSymydobius americanuson paper birch (Betula papyrifera) was investigated experimentally.2Datana ministraandMalacosoma disstriacaterpillars were caged on randomly chosen, undamaged branches until they had eaten 30–50% of the leaf area. Control branches received cages but no larvae.3Alates ofS.americanuswere than caged on the experimental and control branches to assess the effect of chewing damage on colony performance.4Chewing damage had no detectable effect on initiation of alate reproduction, development time, mortality of nymphs or colony growth