The silk fabrics sales volume on current market of China and abroad is tending to increase.Export exchange earnings of natural silk achieve 3 X 109$per year for China in recent years

and fourty percent of the natural silk turnover in the world trade is owned by China. Planting shrubby mulberry on steep slope barren land of more than 25 degrees with new artistry on ridge-trough cultivation of shrubby mulberry on steep slope land.There are 9000~18OOOkg of mulberry leaves per ha that could be produced at hilly region of Shaanxi province;there are 450-900kg of cocoon crop and 300-600 yuan of income that could be obtained from 15~30case of silkworm eggs raised with per ha shurb by mulberry leaves

and 6000-12000 yuan of soil and water conservation benefit per ha could be produced.There are 9.22 X 105ha steep slope land of more than 25 degrees in Shanxi province.On these land

cereal crops must not be cultivated according to Chinese soil and water conservation law.There are 4.33 X 105ha of shrubby mulberry on rideg-trough field could be developed

which will not share the land with grain and other economic crops.Agricultural

industry and business tax could be achieved to the amount of 1.53 X 1010 yuan.At the same time of gaining foreign exchange for homeland

2.6X109~5.2X109yuan of soil and water conservation benefit could be gotten.