ABSTRACT This article is a summary of past accomplishments by a number of entomologists working in the South African macadamia nut industry, on the Heteroptera complex. A range of aspects regarding the biology and subsequent control of these intractable pests are discussed. A short overview of chemical control strategies as well as the current status regarding biological control is provided. An exciting addition to conventional biological control is the usage of bats as predators. Provisional results indicate that this option may be considerably more practical than previously anticipated as some bat species routinely prey on various heteropterans. An overview regarding the species complex affecting macadamia as well as the relative seasonal abundance of most important phytophagous heteropteran species are discussed. This work also relates to monitoring and subsequent spray decision support. Although various trap crops were investigated in the past by a range of researchers, none of these plants did lure any of the most economically important stink bugs in appreciable numbers. The effects of tree density as well as tree height on stink bug populations were investigated and recommendations are given regarding the manipulation of these parameters to the detriment of stink bugs. Strong edge effects were observed, early in the production season when stink bugs initially migrate into macadamia orchards. Early treatment of orchard perimeters is suggested as a possible environmentally friendly alternative method to full blanket sprays currently in use. The recent quantification of a shift in sensitivity towards synthetic pyrethroids indicates that alternative, more environmentally-benign control techniques should be investigated. A brief guideline for some of these ideas as well as a critical evaluation of the current status of IPM in the South African macadamia industry is provided.
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