1. School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
2. Swiss Federal Research Institute WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
3. SCION (New Zealand Forest Research Institute), PO Box 29237, Christchurch, New Zealand
4. Department of Electrical and Computer Engineering, University of Canterbury, Private Bag 4800, Christchurch, New Zealand