Electrical migration of exogenous mineral ions through green sapwood of Pinus sylvestris L. (Scots pine)

The electrical migration was studied of several cations passing longitudina lly through cylindrical samples of green sapwood of Pin us sylvestris L. un der the influence of an applied electric field. This led to values for the hindered ionic conductances within the wood of the cations Li+, K+ and Cu2 which were compared with data obtained previously (Simons et al., 1998) fo r several endogenous cations. There was satisfactory agreement for the cond uctance of the potassium ion, the only one to be determined by both methods . Copper ions were found to possess a higher conductance within the wood th an calcium or magnesium, a factor relevant to its use as a wood preservativ e. Visual observation of the location of the blue-green colouration produce d in the wood by copper ions indicated that they migrated via longitudinal resin ducts and tracheids. Elution and transport experiments were also carr ied out with sapwood which had been flushed with water, Li2SO4 or CuSO4 sol ution.