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Soil Classification

Key to the Cowardin Classification System
 

The structure of the Cowardin classification system is hierarchical, progressing from systems and  subsystems at the most general levels to the classes, subclasses, and modifying terms. The map codes read from left to right (general to specific) as follows:

 
System-Subsystem-Class-Subclass-Modifier
Example: L1AB4H
 
(L=System, 1=Subsystem, AB=Class, 4=Subclass, H=Modifier)
* As modified for the Illinois portion of the National Wetlands Inventory. Any missing numbers are due to the lack of those habitat types in Illinois.
 
 
SYSTEM: PALUSTRINE (P)
SUBSYSTEM: There are no subsystems in the palustrine system
CLASS:
AB - Aquatic Bed
SUBCLASS:
1. Algal
2. Aquatic moss
3. Rooted vascular
4. Floating vascular
6. Unknown surface
EM - Emergent
SUBCLASS:
1. Persistent
2. Non-persistent
FO - Forested
SUBCLASS:
1. Broad-leaved deciduous
2. Needle-leaved deciduous
5. Dead
6. Deciduous
OW - Open Water
SUBCLASS: There are no subclasses in this class
SUBCLASS:
1. Broad-leaved deciduous
3. Broad-leaved evergreen
5. Dead
SUBCLASS: There are no subclasses in this class
US - Unconsolidated Shore
SUBCLASS:
2. Sand
 
SYSTEM:            LACUSTRINE (L)
SUBSYSTEM: 1 -Limnetic
CLASS:
AB - Aquatic Bed
SUBCLASS:
3. Rooted Vascular
4. Floating Vascular
OW - Open Water
SUBCLASS: There are no subclasses in this class
SUBCLASS: There are no subclasses in this class
 
SUBSYSTEM : 2 -Littoral
CLASS:
AB - Aquatic Bed
SUBCLASS :
3. Rooted Vascular
4. Floating vascular
EM - Emergent
SUBCLASS:
2. Non-persistent
OW - Open Water
SUBCLASS: There are no subclasses in this class
RS - Rocky Shore
SUBCLASS: There are no subclasses in this class
UB - Unconsolidated Bottom
SUBCLASS: There are no subclasses in this class
SUBCLASS: There are no subclasses in this class
SYSTEM: RIVERINE (R)
SUBSYSTEM: 2 - Lower perennial
CLASS:
AB - Aquatic Bed
SUBCLASS:
4. Floating Vascular
SUBCLASS:
1. Persistent
2. Non-persistent
RB - Rock Bottom
SUBCLASS:
1. Bedrock
2. Rubble
OW - Open Water
SUBCLASS: There are no subclasses in this class
SB - Streambed
SUBCLASS: There are no subclasses in this class
SUBCLASS: There are no subclasses in this class
US - Unconsolidated Shore
SUBCLASS: There are no subclasses in this class
SUBSYSTEM: 3 -Upper perennial
CLASS:
SUBCLASS:
1. Algal
RB - Rock Bottom
SUBCLASS: There are no subclasses in this class
SUBCLASS: There are no subclasses in this class
SUBSYSTEM: 4 - Intermittent
CLASS:
SB - Streambed
SUBCLASS: There are no subclasses in this class
 
MODIFIER (Any water regime or special modifiers listed can be used in any system in the classification).
Water Regime:
A - Temporarily Flooded
B - Saturated
C - Seasonally Flooded
F - Semipermanently Flooded
G - Intermittently Exposed
H - Permanently Flooded
J - Intermittently Flooded
K - Artificially Flooded
U - Unknown
Z - Intermittently Exposed / Permanent
Special Modifier:
b - Beaver
d - Partially drained/ditched
f - Farmed
h - Diked/Impounded
r - Artificial substrate
s - Spoil
x - Excavated