Comment:

Silt Cover is the extent that substrates are covered by a silt layer (i.e., a 1 inch thick or obviously affecting aquatic habitats). Silt cover differs from the embeddedness metric in that it only considers the fine silt size particles whereas fine gravels, sands, and other fines are considered in assessing embedded conditions. Silt Heavy means that nearly the entire stream bottom is layered with a deep covering of silt. (pool/glides and all but the fastest areas of riffle/runs). Moderate means extensive covering by silts, but with some areas of cleaner substrate (e.g., riffles). Normal silt cover includes areas where silt is deposited in small amounts along the stream margin or is present as a “dusting” that appears to have little functional significance. If substrates are exceptionally clean the Silt Free box should be checked.