S3. 5 cm Mucky Peat or Peat

For use in LRRs F and M; for testing in LRRs K, L, and R.

A layer of mucky peat or peat 5 cm (2 inches) or more thick with value of 3 or less and chroma of 2 or less, starting at a depth ≤15 cm (6 inches) from the soil surface, and underlain by sandy soil material.

User Notes: Mucky peat (hemic soil material) and peat (fibric soil material) have a minimum organic carbon content of 12 to 18 percent, depending on the content of clay. Organic soil material is called peat if virtually all of the plant remains are sufficiently intact to permit identification of plant remains. Mucky peat is at an intermediate stage of decomposition between peat and highly decomposed muck. To ascertain if mucky peat and/or peat are present, determine the percentage of rubbed fibers.