Thanks much for the tips! Cell size is 1ft so fairly straightforward. I also got some hints elsewhere that led me to perform following general steps. Generate surface/slope raster Generate aggregated slope raster to give general flow direction arrows Generate surface/aspect raster from aggregated raster, then changed symbol to a flow arrow that rotates to direction of slope. This allows for easy indication of slope direction for later tracing. Create reclass raster of steep slopes over 40% so that I can create a mask of only steep slope areas Use the reclass to extract a mask of the surface Generate Hydrology/flow direction and flow length from the masked surface Now I had a raster of flow length only of steep slopes which I shaded with desired break values. Flow length is calculated along the slope starting from zero and counts up with each cell. This is fine but I need to define the whole region of the slope whenever the length is over the 25ft. Being this close, and since the area was limited enough, I just traced polygons over the appropriate regions using the flow direction arrows as a guide to defining the edges of the slope. Perhaps you have better ideas of how to arrive at the end result like maybe a mathematical expression that would weed out the steep slope areas that didn't have the threshold length, but this worked well enough for me.
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