Abstract: The biomass and its allocation of the young plantation of Rhus chinensis and R. punjabensis was determined with the average standard tree method. According to the data From 22 standard trees of different basal diameter classes, the following regression equations to estimate the biomass of each organs for Rhus chinensis and R. punjabensis were described from single plant : W= aD^b, W= a( D²H )^b. With signi ficant correlation coefficients 0. 970 0~
0.998 2, small standard error 0.019 5~ 0.051 3, the equations had practical values. The results obtained showedthat the total biomass the gallaphid summer host plants stand in three- year old is 1 540. 6 g/m², among which thebiomasses of tree layer , understory layer and litterfall are 1 291.0 g/ m²
, 157.0 g/ m², 92. 6 g/m² respectively. Thebiomass components ratio of each organ is trunk ( 50.7%) > leave ( 20.9% ) > root ( 14.9%) > branch ( 13.5%) .

Key words: Rhus chinensis, R. punjabensis, biomass