ECONOMICS OF PREPARATION OF POLES FROM INTERMEDIATE YIELDS IN PLANTATIONS OFPINUS RADIATAD. DON

Abstract

SUMMARY The cost of preparing poles from intermediate cuttings in plantations of P. radiata have been analyzed by time studies carried out in the State Forest Reserves Kraaifontein and Franschhoek in the Western Cape. Preparation times at Franschhoek are higher than that at Kraaifontein, the difference increasing with the size of the trees. For trees of a given DBH, the utilizable volumes in these plantations differ insignificantly, but the distribution of these volumes over pole and log classes at Kraaifontein is entirely different from Franschhoek. The value of timber, delivered roadside, at Kraaifontein increases with the size of the tree up to a DBH of 6 inches and decreases from there on. At Franschhoek the value of the timber decreases from a DBH of 4 inches. The stumpage values show a similar trend and the differences between these plantations demonstrate the importance of the optimum preparation of poles and sawlogs. Pinus canariensis is the main coniferous species yielding high quality poles. In the Western Cape and Cape Midlands, poles are also prepared in plantations of P. pinaster and P. raduua. In the Transvaal and Zululand, strength classes A and AA poles are produced in Eucalyptus plantations with E. paniculata and E. cloeziana as main species and strength class B poles from E. saligna.