E horizon.
E horizon. The layer commonly near the surface below an A horizon and above a B horizon. An E horizon is most commonly differentiated from an overlying A horizon by lighter color and generally has measurably less organic matter than the A horizon. An E horizon is most commonly differentiated from an underlying B horizon in the same sequum by color of higher value or lower chroma, by coarser texture, or by a combination of these properties;
Source
30 CFR § 701.5
Scoping language
As used in this chapter, the following terms have the specified meanings, except where otherwise indicated: