The Cu and Ni tolerance of 3- to 5-year-old cuttings of crowberry (Empetrum
nigrum) were tested in controlled conditions. Six levels of Cu (0.1-100 mg
l(-1)), five levels of Ni (0-100 mg l(-1)) and nine levels of Cu + Ni were
applied. The elongation of the shoots, new shoot and root dry weights indi
cated an adverse effect of increasing Cu and Ni concentrations. At low Cu l
evels the addition of Ni decreased the dry weights more than at high Cu lev
els. The results show that E. nigrum accumulated high concentrations of Cu
and Ni mainly in old stem tissue, which contained a maximum of over 3000 mg
kg(-1) Cu and 1000 mg kg(-1) Ni. The concentrations of Cu and Ni in E. nig
rum were higher than those measured in plants growing in areas near to Cu-N
i smelters, but the accumulation pattern was similar. The survival of the c
uttings was not affected suggesting that E. nigrum possesses an internal he
avy metal tolerance. (C) 2000 Elsevier Science Ltd. All rights reserved.