30. Group of Soil Series No.30

This group of soils is well drained, deep, high weathered, fine-textured that occurs on mountainous areas in the northern part of Thailand. Most of the soils developed from intermediate rocks. Soil fertility is moderate. Soil reaction is strong acid. Soils in this group are Chiang San (Ce) and Doi Pui (Dp) series.                In general, this group of soil is covered with mountainous evergreen forest but parts of them had been destroyed by shifting cultivation.

Problems : Low fertility, lack of water in dry season and soil erosion on steep slope, strong acid in some places.

Management for upland crops or vegetables : Upland crops or vegetables will grow better in leveling ground. Application of 1-2 ton/rai compose fertilizer or animal manure or mixed green manure (broadcast 8-10 kg/rai sword bean , 6-8 kg/rai cow pea or 4-6 kg/rai Crotalaria juncia) and mix with soils before flowering. Chemical or liquid LDD fertilizer will also be applied according to recommendation . Plants should be grown on the contour or strip cropping with mulching. Soil should be conserved by vetiver around the areas. Farm ponds are recommended to preserve water to be used in dry season.

Management for orchard : Soil preparation in 50*50*50 pit is to mix 15-25 kg compose fertilizer or animal manure. Conserve the soils by cover crops, mulching, and contour or fencing the tree with vetiver. Application of compose fertilizer or animal manure with chemical or liquid LDD fertilizer at vegetative growth, before and after harvesting. Farm ponds are recommended to preserve water to be used in dry season.