We selected Gaojiagou and Yuanzhishan in Mizhi county as the typical area to the Southern Yulin Hilly and Gully

and built fruit tree introduction and observation plantation. In early 80s

we introduced 114 tree species and 278 varieties

which are fallen into 67 genera and 34 families. Through fourteen years natural selection

47 species and 106 varieties are selected which are fallen into 16 families and 32 genera and suitable to grow in this area and with good economic benefit. During 1987-1993

soil cannot run off the mountain and water cannot flow out the river in the arboretum

and the sand is decreased by 104 874 t/(k㎡.a). The water con-tent in 0~10 cm forest soil of Pinus tabulaeformis

Robinia pseudoacacia and peach is 6.8%~59.2% more than that farm soil. But below 11 cm the water content is to a decreasing tendency. The water content in 0~10 cm forest soil of apricot

Eleagnus angustifolia and Caragana microphylla is 16.4%~33.8% less than in farm land. Apple s economic benefit is the highest in all species

the per hectare output value of apple was 14579 yuan in 1993-1994

which is 3.86 folds higher than potato.