Evergreen (plant) - Retaining its leaves at the end of the growing season and usually remaining green 

 through the winter. 



Facultative species - Species that can occur both in wetlands and uplands; there are three subcategories of 

 facultative species: (l) facultative wetland plants (FACW) that usually occur in wedands (estimated proba- 

 bility 67-99%), but occasionally are found in nonwedands, (2) facultative plants (FAC) that are equally 

 likely to occur in wedands or nonwedands (estimated probability 34-66%), and (3) facultative upland 

 plants (FACU) that usually occur in nonwedands (estimated probability 67-99%), but occasionally are 

 found in wedands (estimated probability 1-33%). 



Fern allies - A group of nonflowering vascular plants comprised of clubmosses (Family Lycopodiaceae), 

 small clubmosses (Family Selaginellaceae), and quillworts (Family Isoetaceae). 



Fibrisis - Organic soils (peats) in which plant remains show very litde decomposition and retain their origi- 

 nal shape; more than two-thirds of the fibers remain after rubbing the materials between the fingers. 



Hooded - A condition in which die soil surface is temporarily covered with flowing water from any 

 source, such as streams overflowing their banks, runoff from adjacent or surrounding slopes, inflow from 

 high tides, or any combination of sources. 



Flooding, frequent - Flooding is likely to occur often during usual weather conditions (i.e., more that a 50 

 percent chance of flooding in any year, or more than 50 times in 100 years). 



Flora - A hst or manual of all plant species that may occur in an area. 



Fluvents - Roodplain soils, characterized by buried horizons and irregularly decreasing amounts of organic 

 matter with depth. 



Forbs - Broad-leaved herbs, in contrast to bryophytes, ferns, fern allies, and graminoids. 



Frequency (of inundation or soil saturation) - The periodicity of coverage of an area by surface water or 

 saturation of the sod; it is usually expressed as the number of years the soil is inundated or saturated during 

 part of the growing season of the prevalent vegetation (e.g., 50 years per 100 years) or as a 1-, 2-, 5-year, 

 etc., inundation frequency. 



Frequency analysis - A method of evaluating vegetation in an area by establishing a transect and counting 

 the occurrences of plant species at various sampUng points along die transect. 



Frequency of occurrence - The number of times a given plant species occurs at sample points along a tran- 

 sect. 



Gleization - A process in samrated or nearly saturated soils which involves the reduction of iron, its segre- 

 gation into motdes and concretions, or its removal by leaching from the gleyed horizon. 



Gleyed - A soil condition resulting from gleization which is manifested by the presence of neutral grey, 

 bluish or greenish colors dirough die soil matrix or in motdes (spots or streaks) among other colors. 



Graminoids - Grasses (Family Gramineae or Poaceae) and grasslike plants such as sedges (Family Cypera- 

 ceae) and rushes (Family Juncaceae). 



Ground water - That portion of the water below the surface of the ground whose pressure is greater than 

 atmospheric pressure. 



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