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<br />Table 6.--Values of n for different types of vegetation <br />on overbank areas <br />[From Chow, 1959] <br /> <br />n value <br /> <br />Overbank cover <br /> <br />Minimum <br /> <br />Normal <br /> <br />Maximum <br /> <br />A. <br /> <br />Pasture, no brush: 1 <br />1. Short grass-------------------- 0.025 0.030 0.035 <br />2. High grass--------------------- .030 .035 .050 <br />Cultivated areas:1 <br />1. No crop------------------------- .020 .030 .040 <br />2. Mature row crops---------------- .025 .035 .045 <br />3. Mature field crops------------- .030 .040 .050 <br />Brush: 1 <br />1. Scattered brush, dense weeds--- .035 .050 .070 <br />2. Sparse brush and trees, in <br /> winter----------------------- .035 .050 ,060 <br />3. Sparse brush and trees, in <br /> summer----------------------- .040 .060 .080 <br />4. Medium to dense brush, in <br /> winter----------------------- .045 ,070 .110 <br />5. Medium to dense brush, in <br /> summer---------------------- .070 .100 .160 <br /> <br />B. <br /> <br />C. <br /> <br />D. Trees <br /> 1. Dense growth of willows, summer, <br /> straight--------------------- .110 .150 <br /> 2. Cleared land with tree stumps, <br /> no sprouts------------------- .030 ,040 <br /> 3. Same as above, but with dense <br /> growth of sprouts------------ .050 .060 <br /> 4. Dense stand of timber, a few <br /> down trees, Ii ttle undergrowth, <br /> flood stage below branches--- .080 .100 <br /> 5. Same as above, but with flood <br /> stage reaching branches------ .100 .120 <br /> <br />.200 <br /> <br />.050 <br /> <br />,080 <br /> <br />.120 <br /> <br />.160 <br /> <br />lShallow depths accompanied by an irregular ground surface in pasture- <br />land or brushland and by deep furrows perpendicular to the flow in cultivated <br />fields can increase n values by as much as 0.02. <br /> <br />40 <br />