Use of needle epicuticular wax chemical composition in the early diagnosis of Norway Spruce (Picea abies (L.) Karst.) decline in Europe

To evaluate the potential of wax composition in the early detection of tree decline wax composition was analysed on needles collected from Norway spruce trees growing at 12 European sites representing 7 different “pollution climates” (SO2, NOx, H+). Cluster analysis successfully grouped trees by “pollution climates” based on wax composition analysed by GC. Over 70% of total variance was accounted for in the first three eigenvalues of the correlation matrix. German sites were segregated from Netherlands and UK sites. Sites receiving highest N deposition were tightly clustered as were sites receiving lowest pollutant loads. Epicuticular wax chemical composition has potential as an early indicator of change in tree condition due to air pollutant impact.