Farmers often grow kale forage for winter grazing of cattle; however, it has been commonly observed that calculated kale yields (target feed) do not match actual production. Lincoln Agritech’s Precision Agriculture Group has investigated the factors that caused these differences and has employed methods to estimate kale yield potential by understanding these factors, farmers can potentially increase their land efficiency by defining management zones to maximise yields and minimise fertilizer applications.
Lincoln Agritech’s researchers investigated the spatial heterogeneity of growth conditions and varying yield levels within kale fields by using multispectral aerial imagery analysis to assess the canopies. The resulting imagery of the results was used to calculate the “Green Normalised Difference Vegetation Index” (GNDVI), which correlated well with kale yield variation.
The results to date have been very promising and showed that these methods were able to estimate yield with good accuracy. Significant spatial variability in the plant vigour within and across fields was also observed. The results were presented at the 2015 Fertiliser Lime Research Centre Workshop.
This research was funded by an Agribusiness Innovation Grant from the Agricultural and Marketing Research and Development Trust (AGMARDT) and contributions from SYNLAIT Farms.