A vineyard sprayer was calibrated using a lamellae
patternator to produce either a “canopy pattern”, derived
from the canopy outline, or a “projection pattern”,
derived from projection of the canopy crosssection
in the directions of the spray fluxes. Both calibration
methods were compared with nozzle adjustment
in the field, and applied in a hedgerow vineyard,
at beginning of flowering and at full foliage development
(berries pea-sized). Spray deposits at different
heights on the canopy were determined by colorimetry,
using a water-soluble dye (Tartrazine) as a tracer.
The results showed that the “projection pattern”
can be recommended for a general sprayer calibration
performed at a public test centre with reference to a
full foliage growth stage of the vine, but methods for
sprayer calibration in the field are also necessary, owing to the difficulty of forecasting the canopy size and geometry at the earlier stages.
