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Table l.--Adjustment factors for the determination of n values for the entire channel--Continued Channel conditions n value adjustmentl Example Small 0.002-0.010 I' Medium 0.010-0.025 :. Channel vege- tation, 04' Large 0.025-0.050 Very large 0.050-0.100 Dense growths of flexible turf grass, such as Bermuda, or weeds growing where the average depth of flow is at least two times the height of the vegetation; supple tree seed- lings such as willow, cottonwood, arrowweed, or saltcedar growing where the average depth of flow is at least three times the height of the vegetation. Turf grass growing where the average depth of flow is from one to two times the height of the vegetation; moderately dense stemmy grass, weeds, or tree seedlings growing where the average depth of flow is from two to three times the height of the vegetation; brushy, moderately dense vegeta- tion, similar to 1- to 2-year-old willow trees in the dor- mant season, growing along the banks and no significant vegetation along the channel bottoms where the hydraulic radius exceeds 2 feet. Turf grass growing where the average depth of flow is about equal to the height of vegetation; 8- to lO-year-old willow or cottonwood trees intergrown with some weeds and brush (none of the vegetation in foliage) where the hydraulic radius exceeds 2 feet; bushy willows about 1 year old intergrown with some weeds along side slopes (all vegetation in full foliage) and no significant vegetation along channel bottoms where the hydraulic radius is greater than 2 feet. Turf grass growing where the average depth of flow is less than half the height of the vegetationj bushy willow trees about 1 year old intergrown with weeds along side slopes (all vege- tation in full foliage) or dense cattails growing along channel bottom; trees intergrown with weeds and brush (all vegetation in full foliage). 1.00 Ratio of the channel length to valley length is 1.0 to 1.2. Degree of Minor meanderinglt m (Adjustment Appreciable values apply to flow con- Severe fined in the channel and do not apply where down- valley flow crosses meanders.) 1.15 1.30 Ratio of the channel length to valley length is 1.2 to 1.5. Ratio of the channel length to valley length is greater than 1.5. lAdjustment for cross-section irregularitiest channel variations, effect of obstructions, and channel vegetation are added to the base n value (tables 2 or 5 or the prediction equations) before multiplying by the adjustment for degree of meandering. 17