Depth to Restricted Layer

A ''restrictive layer'' is a nearly continuous layer that has one or more physical, chemical, or thermal properties that significantly impede the movement of water and air through the soil or that restrict roots or otherwise provide an unfavorable root environment. Examples are bedrock, cemented layers, dense layers, and frozen layers. This theme presents the depth to any type of restrictive layer that is described for each map unit. If more than one type of restrictive layer is described for an individual soil type, the depth to the shallowest one is presented. If no restrictive layer is described in a map unit, it is represented by the ''greater than 200'' depth class. This attribute is actually recorded as three separate values in the database. A low value and a high value indicate the range of this attribute for the soil component. A ''representative'' value indicates the expected value of this attribute for the component. For this soil property, only the representative value is used.