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This study was designed to evaluate the performance efficiency of the commercial wild blueberry harvester for fruit losses during harvesting. Two wild blueberry fields were selected in central Nova Scotia, Canada. A 3 x 3 factorial experiment was constructed to examine the joint effect of ground speed and header revolution per minute (rpm) on picking efficiency of the harvester. Eighty one yield plots (0.91 x 3 m) were selected randomly in each field. The field boundaries, bare spots, weeds and yield plots were mapped with a real-time kinematics global positioning system (RTK-GPS). The harvester was operated at specific levels of ground speed (1.20, 1.6 and 2.0 km h -1 ) and header rpm (26, 28 and 30) to collect total fruit yield, un-harvested berries on the plants, berries on the ground, and berries through blower, from each plot within selected fields. The treatment combinations of the chosen factors were assigned randomly within selected fields. The slope, plant height, and fruit zone were also recorded manually from each plot. The results of classical statistics suggested that the pre-harvest fruit losses were lower in early season of harvesting. Un-harvested berries on the plants and losses through blower were significantly lower than losses on the ground for selected fields. Significant relationship between the fruit yield and total losses suggested that losses during harvesting were linear function of fruit yield within selected fields. Factorial analysis of variance (ANOVA) showed that ground speed, header rpm and their interaction were found to have significant impact on the picking efficiency of the harvester. Results of means comparison showed that a combination of 1.2 km h -1 and 26 rpm resulted in significantly lower losses when compared with other treatment combinations. Results also revealed that an ideal combination of ground speed and header rpm can minimize the fruit losses during harvesting, which will increase harvestable yield and ultimately enhance farm profitability.

Existing commercial variable rate granular (VRG) fertilizer spreader change fertilizer rates in different management zones using global positioning system-guided prescription maps without considering unevenly distributed bare spots and weed patches in wild blueberry fields. The modifications in the existing spreader were made to control each pair of nozzles independently to avoid excessive fertilization in bare spots and weed patches. For this purpose, six I¼Eye digital color cameras were incorporated on the boom (6.21 m wide) in front of the tractor. Custom software installed in the computer was capable of processing the images to detect weeds, bare spots and blueberry plants in real-time and sending signals to the 8-channel variable rate controller (VRC). The VRC then sends the signal to solenoid valves, which in turn closes the pair of nozzles which is directly above the bare spot or weed patch. This study was designed to evaluate the modified VRG (MVRG) fertilizer spreader for spot application of fertilizer only in plant areas. A preliminary test using clay filler as the applied material was conducted at the selected field and 7.3 m wide and 60 m long track was made in the field. Twelve artificial bare spots were made in the selected track using orange colored tarps. Equal numbers of weighed rat catchers (i.e. 12) were placed on artificial bare spots and grass. The MVRG fertilizer spreader was operated on variable rate (VR) mode (detection and no application of clay filler on bare spots). The rat catchers were collected and re-weighed. The same procedure was repeated for uniform (UN) application mode of the system. The results of paired t-test showed significant difference (p-value