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Amount of vegetation (n4)-- (continued) f-' f-' Medium Turf grass growing where the average depth of flow is from one to two times the height of the vegetation; moder- ately dense stemrny grass, weeds, or tree seedlings growing where the average depth of flow is from two to 0.010-0.025 three times the height of the vegetation; brushy, moder- ately dense vegetation, similar to 1- to 2-year-old willow trees in the dormant season, growing along the banks and no significant vegetation along the channel bottoms where the hydraulic radius exceeds 2 feet. Large Turf grass growing where the average depth of flow is about equal to the height of vegetation; 8- to 10-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. 0.025-0.050 Very large Turf grass growing where the average depth of flow is less than half the height of the vegetation; bushy willow trees about 1 year old intergrown with weeds along side slopes (all vegetation in full foliage) or dense cat- tails growing along channel bottom; trees intergrown with weeds and brush (all vegetation in full foliage). 0.050-0.100 Degree of meander- ingy (Adjust- ment values apply to flow confined in the channel and do not apply where downvalley flow crosses meanders.) (m) Minor Ratio of the channel length to valley length is l.O to l.2. Loa Appreciable Ratio of the channel length to valley length is l.2 to l.5. l.15 Severe l.30 Ratio of the channel length to valley length is greater than l. 5. lIAdjustments for degree of irregularity, variations in cross section, effect of obstructions, and vegetation are added to the base n value (table 1) before multiplying by the adjustment for meander.