Fig. 1 Map of North Island, New Zealand showing approximate locations of sampled profiles. The dashed line shows the general extent of volcanic soils (Molloy, 1988). Profiles 1 and 2 were in Whakarewarewa Forest, near Rotorua. Profile 3 was on the Whangaehu river floodplain, 20 km south of Mount Ruapehu. Profile 4 was 5 km west of Kawerau, Profile 5 was 5 km southwest of Whangamata, and Profile 6 was 20 km north of Napier. Profile 7 is that sampled by Vogeler et al. 1996, where the soil is an ash-influenced loess