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make documenting the role of vegetation on stream flow response at the <br />landscape level a difficult and often misleading task. <br />For example, Burton (1997) used USGS stream flow records to assess the <br />cumulative impact of timber harvest activities (which occurred over a 12- <br />year period) on stream flow from Brownie Creek in Utah. Using the North <br />Fork of Dry Creek as the control, Burton (1997) compared the flow for the <br />pre - harvest period (1951 -1960) with the flow for the harvest/post - harvest <br />period (1961 -1980) for both watersheds and found flow for the 1961 -1980 <br />period was significantly greater on Brownie Creek. He concluded the <br />increase was a response to timber harvest. Troendle and Stednick (1999), in <br />a reanalysis of the same data found moving the streamgage location on <br />Brownie Creek in 1960 was more likely the cause of the abrupt change in <br />measured flow (figure 10). The abrupt flow change Burton (1997) detected <br />did occur, but it occurred entirely in 1960 as an artifact of relocating the <br />streamgage and not a reflection of the timber harvest operations that <br />occurred over the next 12 -year period (1960- 1972). If harvesting were the <br />cause of departure, the change would have been subtle and accumulative <br />over the 12 -year period; opposite of the trend in figure 9. <br />Figure 10 presents a comparison of the cumulative flow from Brownie Creek <br />plotted over that from North Fork Dry Creek. In 1960, an abrupt change in <br />the relationship between the two streams occurred as an artifact of <br />streamgage relocation. Because the line is quite linear from 1960 to 1980, <br />one cannot conclude that further increases in flow occurred as a result of the <br />continuous harvesting activities that occurred from 1961 -1972. If timber <br />harvest caused the change, one would expect to see a gradual arc evident in <br />the double -mass plot (figure 10). <br />Leaf (1999) used a combination of long -term USGS stream flow data and <br />NRCS snow - course data to document what he also considered to be the <br />long -term effect of vegetative re- growth or in- growth, causing diminished <br />stream flow in the North Platte River Basin. Leaf (1999) utilized records <br />from the North Platte River at Saratoga, Wyoming, the North Platte River at <br />Northgate, Colorado, and the Laramie River at Woods Landing, Wyoming. <br />In his Table 3, Leaf (1999) summarized analysis of the three gauge records <br />and documents decreases in flow at all three stream gauging stations. His <br />inference is that increased forest density caused a measurable decrease in <br />stream flow. There is no question that increases in forest density cause a <br />19 <br />