Field inspection may refine previously identified 

 vegetation units, as appropriate. It may be advisa- 

 ble to divide large vegetation units into subunits for 

 independent analysis. {CAUTION: In highly varia- 

 ble terrain, such as ridge and swale complexes, be 

 sure to stratify properly.) Decide which plant com- 

 munity to sample first and proceed to Step 7. 



Step 4. Establish a baseline for locating 

 sampling transects. Select as a baseline one project 

 boundary or a conspicuous feature, such as road, 

 in the project area. The baseline should be more or 

 less parallel to the major watercourse through the 

 area, if present, or perpendicular to the hydrologic 

 gradient (see Figure 4). Determine the approximate 

 baseline length. Proceed to Step 5. 



BASELINE 

 SEGMENT 



BASELINE 

 STARTING 

 POINT 



TRAN- 

 SECT! 



STREAM 



Rgure 4. General orientation of baseline and 

 transects (dashed lines) In a hypothetical project 

 area. The letters "A", "B", "C" and "D" represent 

 different plant communities. All transects start at the 

 midpoint of a baseline segment except the first, which 

 was repositioned to Include community type A. 



Step 5. Determine the required number and 

 position of transects. Use the following to deter- 

 mine the required number and position of transects 

 (specific site conditions may necessitate changes in 

 intervals): 



Divide the baseline length by the number of 

 required transects to establish baseline segments 

 for sampling. Establish one transect in each result- 



Baseline length 



Less than one mile 

 One mile to two miles 

 Two miles to four miles 

 Four miles or longer 



Number of 

 Transects 



3 



3-5 

 5-8 



8 or more* 



'Transect intervals should not exceed 0.5 mile. 



ing baseline segment (see Figure 4). Use the mid- 

 point of each baseline segment as a transect starting 

 point. For example, if the baseline is 1,200 feet in 

 length, three transects would be establishei one at 

 200 feet, one at 600 feet, and one at 1,0(X) feet 

 from the baseline starting point. Make sure that all 

 plant community types are included within the tran- 

 sects; this may necessitate relocation of one or 

 more transect lines or establishing more transects. 

 Each transect should extend perpendicular to the 

 baseline (see Figure 4). Once positions of transect 

 lines are established, go to the beginning of the 

 first transect and proceed to Step 6. 



Step 6. Locate sample plots along the tran- 

 sect. Along each transect, sample plots are esta- 

 blished within each plant community encountered 

 to assess vegetation, soils, and hydrology. When 

 identifying these sample plots, two approaches 

 may be followed: (1) walk the entire length of the 

 transect, taking note of the number, type, and loca- 

 tion of plant communities present (flag the location, 

 if necessary), and on the way back to the baseline, 

 identify plots and perform sampling, or (2) identify 

 plant communities as the transect is walked and 

 sample the plot at that time ("sample as you go"). 

 The sample plot should be located so it is represen- 

 tative of the plant community type. When the plant 

 community type is large and covers a significant 

 distance along the transect, select an area that is no 

 closer than 3(X) feet to a perceptible change in plant 

 community type; mark the center of this area on the 

 base map or photo and flag the location in the field, 

 if necessary. {CAUTION: In highly variable ter- 

 rain, such as ridge and swale complexes, be sure to 

 stratify properly to ensure best results.) At each 

 plant community, proceed to Step 7. 



Step 7. Determine whether normal environ- 

 mental conditions are present. Determine whether 

 normal environmental conditions are present by 

 considering the following: 



36 



