Tolerância ao frio e características silviculturais do cedro-australiano no sul do Brasil

Australian red cedar is a widespread species in Southeast, Midwest and Northeast regions of Brazil, which achieves high productivity. It has wood of excellent quality for noble purposes. However, in Southern Brazil it presents growth adjustment problems due to frost occurrence. The aim of the study was to verify cold tolerance and silvicultural potential of Australian red cedar in two locations in Southern Brazil. Treatments consisted of pure stand of Australian red cedar, and mixed plantation with Mimosa scabrella and Eucalyptus benthamii in Lages, SC and pure stand and under Pinus taeda in Ibiam, SC. For two years after implantation survival, damage by frost, fork/budding, total height and stem diameter were evaluated. Australian red cedar showed serious damage by frost in Lages, dramatically reducing survival and damaging silvicultural characteristics. Growing Australian red cedar under P. taeda in Ibiam presented low mortality due to frost. In this location pure stand also presented low mortality, however, frost effects were considerable. Australian red cedar plantation is not suitable for areas with occurrence of heavy frosts, however, in places with less severe frosts, planting under pine is a potential alternative.