Sweepers can generate dangerous amounts of dust, which creates both an air quality problem and a safety hazard if alongside roads.
With harvest fast approaching, there are simple actions almond growers or their custom harvesters can implement to reduce dust from harvest activities. The following tips are based on findings from Almond Board-funded research and input from equipment manufacturers.
• Sweeper heads should be set at the manufacturer’s factory level so that wire tines are 0.125 inches off the ground. If set too low, dust from the pickup is increased substantially. Wire tines without rubber flaps on sweeper heads can reduce dust, particularly on softer soils.
• Adjusting the blower spouts to match the unique conditions in the field can reduce blower passes. Adding an optional berm brush can also help minimize blower passes under many conditions.
• To reduce dust, adjust sweeper heads and blower spouts, and reduce speeds. When operating near roads, blow rows close to the edge into the orchard to allow dust to filter and settle out.
• Harvester ground speed should be reduced, depending on field conditions. In orchards with loose soils, slower ground speed allows gravity to drop dirt rather than depending solely on fans.
• Under clean orchard conditions, suction fan speed can be reduced on pickup machines to dramatically reduce dust in the field without loss of harvest efficiency.
• When operating near roads or homes, use the trees as a natural filter during harvest by blowing rows close to the edge into the orchard to allow the dust to filter and settle out.