Fine Soils

Question 1

F2: Loamy Gleyed Matrix

Answer 1

A gleyed matrix occupying 60 percent within 0-12 inches

Question 2

F3: Depleted Matrix

Answer 2

A layer that has depleted matrix of 60 percent composition of chroma 2. The layer has to be 6 inches thick if starting after 4 inches below the surface or 2 inches thick if is starts before 4 inches.

Question 3

F6: Redox Dark Surface

Answer 3

A 4 inch thick layer starting at the first 8 inches from the soil surface, must have 5 percent redox concentrations of 3-2 or 2 percent redox concentraions of 3-1

Question 4

F7: Depleted Dark Surface

Answer 4

Redox depletions with a value chroma of 5 or more and 2 or lower in a layer 4 inches thick and occuring before 8 inches in depth

Question 5

F8: Redox Depressions

Answer 5

In depressions subject to ponding, 5 percent redox present is layers 2 inches thick and 4 inches from the surface

Question 6

F10: Marl

Answer 6

LRR: U only. A layer of Marl chroma 5-2 (CaCo3) occurring at a depth of 4 inches from the soil surface.

Question 7

F12: Iron/Manganese masses

Answer 7

LRR: P & T only. Flood plains only. A 4 inch thick layer starting within 8 inches from the soil surface that is comprised of 40 percent chroma 2 soil and has 2 percent concentrations of 3-3 iron/manganese deposits

Question 8

F13: Umbric Surface

Answer 8

A layer that is 10 inches thick and starts within 0-6 inches from the soil surface. The upper 6 inches of the profile must be 3-1 or less and the lower 4 inches has to be the same or darker.

Question 9

F:22 Very Shallow Dark Surface

Answer 9

MLRA: 138, 152A and 154 only. In depressions and flood plains only. If bedrock occurs 0-6 inches from the soil surface than more that half of the profile must be 2.5-1 or darker and the remaining must be 2.5-2 or darker.
If bedrock occurs 6-10 inches, a 4 inch thick layer starting 6 inches from the surface must be 2.5-1 or darker and the remaining soil to bedrock must be 2.5-2 or darker