Air movement near windbreaks and a hypothesis of the mechanism of the accumulation of airborne insects



Different components of wind were measured to leeward of artificial windbreaks to show which most affected accumulations of airborne insects there. Horizontal motion was the most important. Accumulations of small airborne insects in sheltered places are probably caused when the insects are diffused or convected into the recirculating air behind barriers. The concentrations likely to occur theoretically in this way were compared with concentrations measured in the field.