Abstract: Both dusky thrush(Turdus numanni) and Amur corktree ( Phellodendron amurense) are only distributed in East Asia. Dusky thrush pass through or stay at the distribution area of Amur corktree during its migrating or wintering period. The thrush mainly eat fruits of Amur corktree and disperse the seeds at the same time. Amutualism exists between the bird and the tree. The Amur corktree are dispersed mainly by the thrush. Under natural condition, seeds of Amur corktree can not germinate under the mother tree.

Key words: paddy-upland rotation, multiple cropping system, paddy field, weed community.