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• 29. Bank erosion: Bank erosion is a function of factors such as riparian vegetation, permeability of the substrate, and tensile strength and cohesiveness of the soil. Consequently, bank erosion can influence the structure of the stream channel (Leopold and Wolman, 1957). The types of bank material movement, if present, are noted. These types include mass wasting (debris avalanche, rotational failure, and slab failure), and cut-bank scalloping (fig. 9). Indicate the presence of bank erosion for the left and right banks using the following code:

    
                          Debris avalanche                DA  
                          
                          Rotational failure              RF  
                          
                          Slab failure                    SL  
                          
                          Cut-bank scalloping             CB  
                          
                          None                            NO  
  

• 30. Bank substrate: Determine the spatially dominant and subdominant substrate types (described above in number 19) that are present in an area of the bank that is within 2 m of either side of the transect, to the top of the bank. This procedure is done for the left and right banks.
• 31. Bank woody vegetation: The point-centered quarter method is used to evaluate density and dominance of bank woody vegetation (Mueller-Dombois and Ellenberg, 1974). Sampling points are established on both banks at the ends of the transect so as to include dominant bank woody vegetation. Four quarters are established at a sampling point at the intersection of two perpendicular lines, one of which is the transect line (fig. 10). Trees and shrubs are included in the analysis. Trees are distinguished from shrubs in that trees are at least 2 m high and have a diameter at breast height (dbh) of at least 3 cm. The sampled trees or shrubs are identified to species, and the distance from the sampling point to the nearest tree or shrub in each quarter is measured, along with its dbh (fig. 10). To record the species, use a four-letter code based on the first two letters of the scientific name for the genus and the first two letters of the species (for example, "BENI" is recorded for Betu la nigra). Where bank woody vegetation is growing in narrow strips or rows, the two closest trees or shrubs on either side of the sampling point are measured. Where a single tree or shrub has developed many separate trunks, an average dbh for three trunks is recorded, along with the total number of trunks.
• 32. Photodocumentation: Stream conditions at three transects, including the transects at or near the reach boundaries and one transect representative of reach conditions, are photographed. Semipermanent markers are established at these locations to facilitate taking repeat photographs. Color photographs, preferably slides, are taken that include upstream, transect, and downstream views of the channel and should include a scale reference in the image. Use of the same type of film at all sites and at a site over time increases comparability of repeat photographs and reduces variability related to film development. The inclination and aspect of the camera lens are important and are measured with a compass. A level camera is preferred to an inclined one because inclination complicates the perspective of the view and makes accurate duplication of repeat photographs difficult. The aspect of the camera is noted by pointing a compass at the central aiming point in the view and recording th e compass reading. Camera lens size, camera type, exposure, film type, and other appropriate documentation information for taking 35-mm color photographs are recorded on the reach form.