<p style="text-align: justify;"><strong>Aims</strong>: The young alluvial soils of the Wairau Plains, Marlborough, New Zealand, are considered to play an important role in determining this unique wine style. The aim of this experiment was to investigate, within a single vineyard, the impact of soil texture on vine vigour, vine earliness and fruit composition.</p><p style="text-align: justify;"><strong>Methods and results</strong>: Trunk circumference and pruning weights, were greater as the depth to gravel increased. Soil conductivity measurements, using an electromagnetic sensor (EM38) in conjunction with global positioning related well to vine trunk circumference. Where gravels came to the surface, soil temperatures measured at 30 cm depth were consistently higher by 1 to 2 °C (air temperature was unaffected) and vine phenology was more advanced, when compared to the deep silt soils. At harvest, fruit soluble solids and pH were higher and titratable acidity lower when vines grown on shallow soils, but soil type had no significant effect on fruit yield.</p><p style="text-align: justify;"><strong>Conclusions and significance of the study</strong>: Vine phenology during the growing season and fruit composition at harvest but not yield, reflect changes in soil texture over quite short distances within vineyards on the Wairau Plains. Within a vineyard, the higher the proportion of gravelly soils, the more advanced the vine phenology and the riper the fruit and wine style will exhibit riper (more tropical) and lower unripe (herbaceous) characteristics on a particular date.</p>

Background and Aims: Vineyards are variable. However, to date, no spatial analysis of vineyard variability has been conducted in New Zealand. We were interested to quantify variability in a Marlborough vineyard and to produce a spatial platform onto which modelled information on phenology and juice composition could be integrated. Methods and Results: A combination of remote and proximal sensing of vine vigour, direct measurement of trunk circumference, yield mapping and high resolution electromagnetic induction (EM38) soil survey was used to examine vineyard variability in a 5.9 ha Marlborough vineyard planted to Vitis vinifera L. cv. Sauvignon Blanc. Yield variation was little more than twofold, in spite of substantial variation in vine vigour which was associated with variation in the land (soil, topography) underlying the vineyard. Conclusions: A focus on tools that facilitate enumeration of variation in vine vigour may offer the greatest value to Marlborough practitioners interested in adopting Precision Viticulture approaches to grapegrowing and winemaking. EM38 soil survey appeared to be useful for describing vineyard soil variation, but because the soils that predominate over the alluvial Wairau Plains in Marlborough are shallow and stony, very low values of apparent electrical conductivity (ECa) over a narrow range were observed. However, ECa was closely correlated with trunk circumference, an index of vine vigour. In contrast to Australian studies, neither ECa, plant cell density (derived from remotely sensed imagery) nor trunk circumference were good predictors of grapevine yield. It is hypothesised that this is largely a reflection of differences in vine training systems (hand cane pruning in Marlborough vs mechanical pruning in Australia) and the greater degree of selection of buds when vines are hand pruned. Significance of the Study: This is the first such study conducted in New Zealand and provides results that contrast with similar studies conducted in Australia. Nevertheless, the maps produced are expected to provide a valuable platform for a follow-up study aimed at understanding spatial variation in vine phenology and juice composition. The study also highlighted the power of kriging as a means of interpolating useful vineyard maps from relatively sparse, unevenly distributed sampling data.

Published statistics on the spatial variation of fruit quality observed in orchards has been rudimentary to date. Dry matter and fruit weight data were collected spatially within 11 kiwifruit (Actinidia deliciosa var. deliciosa ‘Hayward’) orchards in the Bay of Plenty, New Zealand, to characterize the variability in fruit quality in terms of nonspatial and spatial statistics. Fruit weight was statistically more variable and exhibited a stronger spatial structure than the dry matter data. Individual variograms were derived for each orchard and then all the data were collated into average variograms for both quality attributes. The average variogram parameters were used to determine the optimum spacing for grid sampling to achieve a desired level of confidence when interpolating the data. A grid spacing of 28 m appears suitable for mapping fruit quality, provided sufficient area exists to collect enough points to perform block kriging. Plots of individual orchard and average variograms, and a table of nonspatial and variogram statistics are presented as a reference for future work in this area.

Spray drift continues to be an important issue for commercial pipfruit growers Offtarget agrichemical movement was determined from the Hawkes Bay Focus Orchard on two occasions Canopy development had a major influence on spray drift with 25 times less drift from a fully foliated canopy compared with a dormant canopy The proximity of the sprayer relative to the edge of the sprayed block was an additional major factor influencing spray drift Results are compared with those found in previous New Zealand and overseas studies and management strategies for spray drift minimisation are discussed

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