• STEP 4 - Summarize Available Information on Vegetation. Examine 

 available sources that contain information about the area vegetation. 

 Consider the following: 



a. uses quadrangle maps. Is the area shown as a marsh or swamp? 



~ CAUTION: Do not use this as the sole basis for determining 

 that hydrophytic vegetation is present. 



b. NWI overlays or maps. Do the overlays or maps indicate that 

 hydrophytic vegetation occurs in the area? If so, identify the 

 vegetation type(s). 



c. EIAs, EISs, or GDMs that include the project area. Extract any 

 vegetation data that pertain to the area. 



d. Federal, State, or local government documents that contain 

 information about the area vegetation. Extract appropriate 

 data. 



e. Recent (within last 5 years) aerial photography of the area. 

 Can the area plant community type(s) be determined from the 

 photography? Extract appropriate data. 



f^. Individuals or experts having knowledge of the area vegetation. 

 Contact them and obtain any appropriate information. CAUTION: 

 Ensure that the individual providing the information has 

 firsthand knowledge of the area. 



£. Any published scientific studies of the area plant communities. 

 Extract any appropriate data. 



h. Previous wetland determinations made for the area. Extract any 

 pertinent vegetation data. 



When the above have been considered, PROCEED TO STEP 5. 



• STEP 5 - Determine Whether the Vegetation in the Project Area Is Ade- 

 quately Characterized. Examine the summarized data (STEP 4) and deter- 

 mine whether the area plant communities are adequately characterized. 

 For routine determinations, the plant community type(s) and the domi- 

 nant species in each vegetation layer of each community type must be 

 known. Dominant species are those that have the largest relative basal 

 area (overstory) , * height (woody understory) , number of stems (woody 

 vines) , or greatest areal cover (herbaceous understory) . For compre- 

 hensive determinations, each plant community type present in the 



* This term is used because species having the largest individuals may not be 

 dominant when only a few are present. To use relative basal area, consider 

 both the size and number of individuals of a species and subjectively 

 compare with other species present. 



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