SOME EVIDENCE OF LOSS OF PRODUCTIVITY WITH SUCCESSIVE ROTATIONS OF PINUS RADIATA IN THE SOUTH-EAST OF SOUTH AUSTRALIA

SUMMARY Evidence is presented that second rotation planted stands of Pinus radiata D. Don in South Australia have a lower productivity than first rotation crops on the same sites. After clear felling of unthinned first rotation stands a significant loss of productivity in replanted stands is shown by the remeasurement of a number of permanent sample plots, and also by comparisons of site quality (S.Q.) assessments of first and second rotation crops. The picture with naturally regenerated stands is not clear. One case indicates that there has been no loss of productivity, while two plots suggest that a real loss has occurred. A considerable amount of fundamental and empirical research work has been initiated in South Australia to investigate the causes of this important problem.