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r ~ 26 were judged to be most sensitive to flooding were sand bars, sand beaches, gravel bars, and gravel islands. At each site, from two to four randomly located line transects were run, each starting at the water's edge and extending up the bank, perpendicular to the river. Each line was extended beyond the point at which a change in vegetation or substrate indicated that flooding was no longer a major inf luence. Each transect was thus of different length, but each included the entire flood zone and part of the riparian or upland zones. Plant foliar coverage was measured by the point intercept method. A metal rod was dropped at each 10 cm point along the line. Contact was recorded if the rod touched any living plant tissue. At each point, the surf icial substrate type was also recorded. The class of substrate type was also recorded. The classes of substrate used were silt and clay (determined by feel), sand (less than 2 mm in diameter), gravel (2 mm-l0 cm), cobble (10 cm-30 cm), stone (30 cm-100 cm), boulder (greater than 100 cm), litter, and log. Density of woody perennials was measured in a one meter wide belt transect on the right-hand side of the line (looking up from the water's edge). The number of stems at ground level was recorded for each square meter. Density of herbaceous plants was measured in a 30x30 cm quadrat in the lower left-hand corner of each square meter quadrat in the belt. Relief along each transect was measured using a Suunto PM-5/360 PC hand-held Clinometer. EYom these data, each transect was divided into elevational zones, each representing one-half meter rise above-the water line. Coverage, density, and substrate data fray within each of these zones were combined. Mean, standard deviation, and 95$ confidence intervals (using the normal approximation of the binomial distribution for coverage and the normal approximation of the Poisson distribution for density; Pollard, 1977) were calculated for each parameter within each zone at each site.