This group of soils is well drained and fine-textured that occurs mostly on erosional surface uplands of udic soil moisture regime in the southeast coast and peninsula south. They are commonly low fertility. Soil reaction is strong acid. Most of the land are covered with tree crops such i.e. trees, rubber and oil palm. Soils in this group are Ao Luk (Ak), Huay Pong (Hy), Krabi (Kbi), Kok Kloy (Koi), Lum Phura (Ll), Pak Chun (Pac), Pang Nga (Pga), Puket (Pk), Patiew (Ptu) and Tai Muang (Tim) series.