Wild blueberries are an important horticultural crop native to northeastern North America. Management of wild blueberry fields has improved over the past decade causing increased plant density and leaf foliage. The majority of wild blueberry fields are picked mechanically using tractor mounted harvesters with 16 rotating rakes that gently comb through the plants. The extra foliage has made it more difficult for the cleaning brush to remove unwanted debris (leaf, stems, weeds, etc.) from the picker bars while harvesting. Currently, there is no protocol for adjustment of the brush into the picking teeth for maximum debris cleaning performance while minimizing wear. Research is required to determine the cleaning brush’s acceptable wear limit to allow harvester operators to make better management decisions.

A wild blueberry field was selected in central Nova Scotia to benchmark the performance of different wear levels of debris cleaning brushes. Two-hundred-meter-long test strips were setup and four different brush wear levels were replicated in quadruplicate to study the blueberry yield and harvest time required. Results suggested that the harvesting time was increased by 27.8% when using a brush with a bristle length of 120 mm as compared to a brush with an 87 mm bristle length. The shorter bristle length caused excess buildup of debris in the picker teeth resulting in the operator continually stopping for manual debris removal. Ten-meter long test strips in the same field were replicated in quadruplicate and used to evaluate the amount of debris lodged in the picker teeth using the four different brush wear levels. This experiment was completed in both weedy and non-weedy conditions. Results suggested that both brush wear and weeds in the field increase the amount of debris lodged in the picker teeth. Results from this study were used to develop an optimum brush performance protocol and adjustment guide that operators can use throughout the harvesting season.