We used radar to observe long-distance migration of brown planthopperat Jiangpu in Jiangsu Province during the second half of September

1988.Brownplanthopper dominated the night-flying aerial fauna during the period of observati-ons. Most migrant brown planthopper took off between late afternoon and dusk

cli-mbed to 400 1000m.Trajectory analysis shows that they are dispersing downwind

mainly to the southwest

where insects migrate in the north-easterly winds blowing on the east or south-east sides of a continental anticyclone.centred over northern central China. This direction is ecologically advantageous at this season because it carries the brown planthopper toward areas where survive the winter is possible