58. Group of Soil Series No.58

This group is organic soils in the coastal swamp. Its material is less decomposed with more than 100 cm. depth. The underlying substratum is includes pyretic mud clay. They are very low fertility, nutrient deficiency and extremely acid. Soils in this group is Naratiwat (Nw) series.                Some areas remaine under climax fresh water swamps. Many parts have been opened for agriculture.

Problems : Strong acid, medium layer of organic decomposition texture, permanent flooding but easy to be fired in dry condition, nutrient deficiency and toxicity of some substances, acidic water and lack of fresh water.

Management for rice : Broadcast 1.5-2.0 ton/rai lime and prepare soils with small machine or man power. Acid tolerate rice, drainage and irrigation are recommended. 16-16-8 chemical fertilizer will be applied to the soils, 30-45 days before and after planting.

Management for upland, vegetable crops and orchard : Raised bed to 6-8 meters wide with 1.0-1.5 meters width and 0.5-0.75 meters depth drainage canal with dike to avoid flooding. Broadcast 2.5-3.0 ton/rai over the bed and the canal. Soil preparation in 50*50*50 pit is to mix 250 gm. of rock phosplate with recommended chemical fertilizer for orchard. Apply 2.5-3.0 ton/rai lime if acidity is increased