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Evidence that the opossum is far from harmless to exotic forests is gradually accumulating. In regeneration areas it is particularly fond of Pinus ponderosa leading shoots. In young sapling areas it gnaws large patches from the thinner bark of the upper stem of most pines (though there is as yet no reported case of such damage to Pinus radiata). The result is infrequently a killed leader ; much more frequently a damaged leader which snaps off some years later with the wind. Quite recently, moreover, similar damage to larch was noted, when the leafless larch, if scattered in mixture amongst pines, appeared to attract the animal's attentions. Deer were most numerous in Blue Mountains State Forest (Southland), but, owing to increased duties necessitated by the supervision of relief labour, forest employees were not able to engage in deer destruction on a comprehensive scale. In all, 424 fallow deer were destroyed at this station. Forest Parasite Biology. The vagaries of the climate referred to in a preceding paragraph were reflected in the parasite virulence. The absence of late frosts and the wet open spring were welcome changes from the past seasons. Phomopsis incidence was thus light in State forests, partly owing to weather conditions and partly owing to the hygienic measures that have been applied to critical areas over the past three years. On the other hand, Diplodia, pinea, assisted by the drought conditions that prevailed in parts of the country, was extremely noticeable, particularly on light, shallow soils overlying compacted gravels. In similar situations the drought was directly responsible for the deaths of large areas of pines planted during the preceding winter. No dangerous outbreak of insect pests was reported : but it was noticeable that the indigenousforest insect population enjoyed a good brood year, and the polyphagous lepidopters, which always inhabit the forest edges, were more than usually noticeable on the exotic shade-bearing species which are being worked into recently exploited areas. Similarly, at least one exotic forest in Nelson encountered one of the periodic peak populations of the two native green chafer beetles, and some defoliation of small areas of exotic conifers was the result. No permanent damage seems likely to result. The most spectacular outbreak of insects was only indirectly connected with forestry. The native moth, Mecyna maorialis, completely defoliated hundreds of acres of Lupinus arboreus, particularly on the south-west coast of the North Island. The host plant is widely used as a secondary sand-collector on dune areas on the zone immediately behind the marram zone. For miles of the coast-line every plant of the lupin was completely defoliated and killed, and owners of dune properties were apprehensive of grave disaster. There is, however, an ample supply of natural seedlings of the lupin everywhere ; and as the destroyer is a native moth normally common and with a wide food-range it is believed tha,t the occurrence was merely that of a plague-year," due perhaps in part to the very dry summer, and certainly not likely to be repeated before the lupin population has regained its former vigour. Investigational work was continued with unchanged staff at the Cawthron Institute (entomology) and the Plant Research Station (mycology). The entomologist continued quarantine studies on parasites of eucalypt pests and inaugurated a new series of studies on native Platypus beetles (" pinhole borers "). Work on Hylastes ater and Sirex noctilio and their potential parasites was carried on ; but, although there were reports of recapture of parasites from some field stations, no unqualified statements of marked success on a large scale can yet be made. The mycologist pursued mainly the work on Phomopsis disease of exotic conifers, and a bulletin on the disease was published (State Forest Service Bulletin No. 7). Systematic work on a similar nature on the other common conifer disease due to Diplodia pinea was begun and was carried to such a stage that a bulletin will be ready for publication in the incoming year. Work on this led into work on timber staining fungi, which will be the next subject of study. These studies will be correlated with entomological work on wood-boring insects, which will be undertaken by the entomologist simultaneously. CHAPTER lII.—UTILIZATION. 1. General. The emphasis in forest-utilization work is primarily upon the practical application of available knowledge to the solution of current problems in the timber-producing and wood-using industries. The problem of developing a balanced scheme of utilization for the high-value virgin timber of the indigenous forests and the low-value product of the exotic forest dominates the whole field of forest economy in New Zealand. 2. Logging Technique. Logging operations in the indigenous forests have, since the earliest days of the country, ranked as the most efficient branch of the timber industry, and though the Dominion has lagged behind North America in the use of tractor logging sawmills are now adapting tractor equipment to local conditions and effecting substantial cost-reductions. The continued operation of small sawmills working on exotic thinnings is also developing an improved forest technique in the felling, trimming, and hauling of small logs. The indigenous-forest workers introduced to this class of work still prefer the axe to the saw for both felling and cross-cutting, but the experimental use of various types of European saws usually employed for such work is being persevered with. Although not as fast as the axe, they reduce waste to ft minimum and merit exhaustive consideration.

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