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In an investigation of the composting of eucalypt bark, a bench‐scale composter was designed to provide strict control over air composition, moisture content, temperature, and mixing. The composter consisted of six 4‐L capacity gas‐tight units of PVC plastic, each of which was provided with a mixing paddle coupled to a common drive. Natural temperature rise was simulated by having the units immersed in a water bath, with the temperature increased at rates consistent with those observed in large‐scale compost heaps. This provided a comparatively inexpensive versatile system, with rates of CO2, NH3, CH4, and H2S production and O2consumption manually monitored by gas chromatography. The reproducibility of the system was as good as the best reported.

The encyrtid parasite Anagyrus saccharicolaTimberlake was introduced into Australia from Hawaii in 1953 as a biological control agent of Saccharicoccus sacchari(Cockerell), the pink sugarcane mealybug, but was believed not to have become established. However, a recent survey has shown it to be widespread in the principal sugarcane growing areas of Queensland and New South Wales. Other natural enemies of S. sacchariinclude the fungus Aspergillus parasiticusSpear and the insect predators, Cacoxenus perspicax(Knab), Coccodiplosissp., Cryptolaemus montrouzieriMulsant and Oplobates woodwardiGross. S. sacchariwas attended by the ants Paratrechinaprobably vaga(Forel), P.prob. bourbonica(Forel), Camponotusprob. chloroticusEmery, Tetramorium bicarinatum(Nylander), Pheidole megacephala(F.) and Iridomyrmexsp.