pie transects, or to Step 15 when determining a 

 boundary between wetland and nonwetland sample 

 plots. {Note: Double check all data sheets to ensure 

 that they are completed properly before going to 

 another plot) 



Step 14. Take other samples along the tran- 

 sect. Repeat Steps 5 through 13, as appropriate. 

 When sampling is completed for this transect pro- 

 ceed to Step 15. 



Step 15. Determine the wetland-nonwetland 

 boundary point along the transect. When the tran- 

 sect contains both wetland and nonwetland plots, 

 then a boundary must be established. Proceed 

 along the transect from the wetland plot toward the 

 nonwetland plot. Look for the occurrence of 

 upland species, the appearance of nonhydric soil 

 types, subtle changes in hydrologic indicators, and/ 

 or slight changes in topography. When such fea- 

 tures are noted, establish a new sample plot and 

 repeat Steps 8 through 12. (Note: New data sheets 

 must be completed for this new sample plot.) If 

 this area is a nonwetland, move halfway back 

 along the transect toward the last documented wet- 

 land plot and repeat Steps 8 through 12, varying 

 plot size as appropriate. (Note: Soils generally are 

 more useful than vegetation in establishing the wet- 

 land-nonwedand boundary, panicularly if there is 

 no evident vegetation break or when FAC species 

 dominate two adjacent areas.) Continue this proce- 

 dure until the wetland-nonwedand boundary point 

 is found. It is not necessary to complete new data 

 sheets for all intermediate points, but data sheets 

 should be completed for each plot immediately 

 adjacent to the wedand-nonwedand boundary point 

 (i.e., one set for each side of the boundary). Mark 

 the position of the wedand boundary point on the 

 base map or photo and place a surveyor flag or 

 stake at the boundary point in the field, as neces- 

 sary. Continue along the transect until the bounda- 

 ry points between all wedand and nonwedand plots 

 have been established. (CAUTION: In areas with a 

 high interspersion of wedand and nonwedand plant 

 communities, several boundary determinations will 

 be required.) When all wetland determinations 

 along this transect have been completed, proceed to 

 Step 16. 



Step 16. Sample other transects and make 

 wetland determinations along each. Repeat Steps 5 

 through 15 for each remaining transect When wet- 

 land boundary points for all transects have been 

 established, proceed to Step 17. 



Step 17. Determine the wetland-nonwedand 

 boundary for the entire project area. Examine all 

 completed copies of the data sheets and mark the 

 location of each plot on the base map or photo. 

 Identify each plot as either wetland (W) or nonwet- 

 land (N) on the map or photo. If all plots are wet- 

 lands, then the entire project area is wetland. If all 

 plots are nonwetiands, then the entire project area 

 is nonwedand. If both wedand and nonwedand 

 plots are present, identify the boundary points on 

 the base map or on the ground, and connect these 

 points on the map by generally following contour 

 lines to separate wetlands from nonwetiands. Con- 

 firm this boundary on the ground by walking the 

 contour lines between the transects. Should ano- 

 malies be encountered, it will be necessary to 

 establish short transects in these areas to refine the 

 boundary, apply Step 15, and make any necessary 

 adjustments to the boundary on the base map and/ 

 or on the ground. It may be wonhwhile to place 

 surveyor flags or stakes at these boundary points, 

 especially when marking the boundary for subse- 

 quent surveying by engineers. 



Point Intercept Sampling Procedure 



4.19. The point intercept sampling procedure is a 

 frequency analysis of vegetation used in areas that 

 may meet the hydric soil and wedand hydrology 

 criteria (see Part II, p. 5). It involves fu^t identify- 

 ing areas that may meet the hydric soil and wetland 

 hydrology criteria within the area of concern and 

 then refining the boundaries of areas diat meet the 

 hydric soil criterion. Transects are then established 

 for analyzing vegetation and determining the pres- 

 ence of hydrophytic vegetation by calculating a 

 prevalence index. Sample worksheets and a sample 

 problem using this mediod are presented in Appen- 

 dices B and D, respectively. 



Step 1. Identify the approximate limits of 

 areas that may meet the hydric soil criterion within 

 the area of concern and sketch limits on an aerial 

 photograph. To help identify these limits use 

 sources of information such as Agricultural Stabili- 

 zation and Conservation Service slides, soil sur- 

 veys, NWI maps, and other maps and photo- 

 graphs. (Note: This step is more convenient to 

 perform offsite, but may be done onsite.) Proceed 

 to Step 2. 



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