Abstract
The emergence of sprangletop, Leptochloa chinensis Nees was investigated under five levels of soil moisure and five times of soil cultivation.
1. Emerged number of the weed was little different from upland field condition to 10cm level of groundwater, but it decreased under the water-saturated condition by half.
2. The duration of emergence differed from time to time of soil cultivation. It was about 50 days in late May, about 30 days in the middle of June, and about 20 days in July-August. This change may be concerned with the dormancy of seeds.
3. The Weed scarcely emerged in the early autumn. This fact may be concerned with the secondary dormancy of seeds.
