The high-altitude wind-borne migration of beet webworm, Loxostege sticticalis, moths with other insects and their short-distance dispersal were observed with a digital scanning radar and twin light-traps (a vertical-pointing searchlight trap operated alongside a ground-based conventional light-trap) in northern China in 2002. Catches in both light traps suggested there were four flight periods of L. sticticalis during our study. The ovarian development stage of females caught in the light traps coupled with radar observations indicated that L. sticticalis migrated to the northeast in early June, whereas locally bred moths dispersed over shorter distances in mid-July and early August. The variation of the area density of insects through time during the spring migration was different from that during the summer dispersal; there was no density peak during spring, but such a peak occurred every evening in summer. Collective orientation by the moths was observed in the spring migration, with the direction of orientation being toward the northeast. In contrast, there was no common orientation in summer. Multilevel layering of migrants was seen every night in our observations in both spring and summer. The layering phenomenon was related to wind speed maxima rather than to temperature inversions when the air temperature was above the threshold for migration.