Classification and Properties of Organic Soils

Abstract

This chapter discusses the salient features and concepts of organic soil classification systems, bog classification, and other related studies dealing with properties of organic soils. The principal objective of organic soil classification is to characterize and organize the most important morphological, physical, and chemical properties of these soils significant to their proper utilization. The criteria used in classifying organic soils include topographical-geographical, surface vegetation, chemical properties, botanical origin, morphology, and genetic processes. Certain physical and chemical properties of organic soils that currently seem most meaningful as criteria in classification are also considered in the chapter. These properties include bulk density, fiber characteristics, pH ash content, and degree of decomposition. The morphological features of organic soil horizons constitute the most important and useful criteria for the classification of organic soils. Adequate characterization of certain diagnostic horizons of an organic soil is the first step in classification. Morphological properties useful in characterizing the horizons of these soils include amount and size of fiber and degree of decomposition determined in several ways. In the classification of organic soils, three types of horizons are considered diagnostic in the highest level (Suborder) in the classification system. These are the fibric, mesic, and sapric horizons.