In spring, tubular wax structures were observed on the needle surfaces
of new Norway spruce needles and also on previous-year needles. In yo
ung plants, as in mature trees, the fusing ana eroding of the wax tube
s on needles of increasing age had taken place in relation to their ex
posure, particularly to wind and precipitation. The quantity of needle
wax and certain fractions of the extracted wax differed in mature tre
es at two field sites and in young clonal plants. No difference in wax
quantity and only small differences in wax composition occurred among
young plants which had undergone different treatments (fumigation wit
h O3, SO2, ambient air, filtered air, or planting at the sites). Envir
onmental effects on wax structure, wax quantity and the presence of ce
rtain compounds in the wax were identified.