Agency Action Plan. An agreement between specific Illinois state
agencies that describes how each agency will comply with the regulations
established in the Interagency Wetland Policy Act of 1989.
Accretion The gradual build-up of
deposited sediments in a wetland.
Adventitious Roots which grow
in unusual places, such as wherever the stem of the plant comes
in contact with the ground.
Aerenchyma Spongy, specialized plant
tissue made of large air-filled intercellular spaces that transport
air from the leaves, and stems to the roots.
Anaerobic The condition of oxygen
Artificial Wetlands (AW) Artificial
and Irrigation-induced Wetland. USDA/NRCS classification of wetlands
with NFSA exemptions. Wetlands in an area that was formerly non-wetland,
but now meets wetland criteria due to human activities, including
wetlands created by an irrigation system on an area that was formerly
Buttressed The state of a tree
trunk being excessively swollen to the height of the usual high
water mark. Typical state of cypress and mangrove trees.
Class Second lowest wetland classification
before modifiers are applied.
CW Converted Wetland. USDA/NRCS classification
of wetlands subject to FSA restrictions. Wetlands drained, dredged,
filled, leveled, or otherwise manipulated for the purpose of, or
to have the effect of, making possible the production of an agricultural
commodity. These lands must have been W, FW, or FWP and not highly
erodible prior to the conversion. They may have been converted by
any activity, including the removal of woody vegetation, that impaired
or reduced the flow, circulation, or reach of water; provided the
conversion activity was such that agricultural production on the
land would not have been possible without its application.
The marking of a boundary on the ground that designates between
wetland and non-wetland areas.
Deposition The gradual accumulation
of sediments over time.
Determination The classification
of a wetland type on a parcel of land.
Discharge Zone An area through which
an aquifer releases excess water.
DOD Department of Defense. Parent agency
for the USACE.
Emergent Plant species that establishes
its roots below normal water level and projects its stems and leaves
above normal water level.
Endangered A classification for
species in low enough populations that they are likely to become
extinct from their natural range.
Extirpated A classification for
species that have become locally extinct.
FAA Farmland Assessment Act. State legislation
allowing farmland taken out of production to be eligible for tax
FAC Facultative Macrophytic plant species
equally likely to occur in wetlands or non-wetlands (estimated probability
FACU Facultative Upland. Macrophytic plant
species that usually occur in non-wetlands (estimated probability
67-99 percent) but are occasionally found in wetlands (estimated
probability 1-33 percent).
FACW Facultative Wetland. Macrophytic
Plant species that usually occur in wetlands (estimated probability
67-99 percent) but are occasionally found in non-wetlands.
Floodflow The flow of a stream at