Coppicing success of young Eucalyptus saligna in Hawaii

Abstract

Coppicing characteristics of felled 3-year-old E. saligna trees growing in Hawaii were evaluated for four DBH classes and two stump-height segments. About 40% of all the stumps had at least one living shoot > 2 cm at the end of the 20-week study period. Tree size before felling had no effect on number of dormant buds available to develop into shoots, sprouting success or length of the longest sprout per stump, but all of these variables were affected by stump-height segment. Standardized 20-cm stump segments above the lowest branch scars (about 34–60 cm above ground) had about double the number of dormant buds, sprouting success and length of the longest shoot per stump than stump segments below the lowest branch scars. Ambrosia-beetle attacks on the stumps were coincidental with coppice development (2–8 weeks after felling), and were less severe on the stumps from the smaller trees and on the upper stump segments. Reasons for the low coppicing success of E. saligna in Hawaii are unknown. The opportunity for coppice (frequency of dormant buds) and the disturbance of coppicing by ambrosia beetles need to be more fully understood before coppicing can be a dependable method of regenerating this species in short-rotation intensive culture plantations in Hawaii.