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Two trellises (single wire and 37 cm wide 'T') and four pruning methods were compared on irrigated Shiraz grapevines, Vitis vinifera at Griffith. The pruning treatments were 'spur', 'rod and spur', 'hare's ear' and 'cane' pruning. Similar trellises and 'spur' and 'cane' pruning were compared on the vigorous cultivar Semillon. Yields were generally increased as node numbers increased. Thus 'T' trellises outyielded single wire trellises for each cultivar. There was no evidence of bud fruitfulness or photosynthetic capacity being increased by the 'T' trellis. Cane pruning generally produced larger crops in the early years of the experiments, but over all years there was little difference between pruning systems on individual vine yields. Cane pruning simply offered a means of increasing the node numbers of young vines. It is concluded that spur pruning, as the cheapest, is the most desirable method although cane pruning may be necessary in the future for mechanical harvesting.

Radiance data collected by Landsat were used to derive wheat production forecasts. Radiance data at three stages of wheat growth in 1976 for the Tamworth region of the New South Wales wheat-belt were analysed by multivariate statistical methods to discriminate between paddocks that had been sown with wheat and those that had not, and to relate radiance to wheat yield. A discriminant function was derived that classified the paddocks, and a regression equation was derived to predict yields of wheat paddocks. Although data were not available for the green vegetative phases of growth, intrinsic testing of classification and yield prediction indicated high accuracy, although extrinsic testing indicated that they were less accurate. Assuming that data are available in future seasons at the vegetative stages, Landsat has a great potential for improving wheat forecasts in Australia.

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