Design

Region

N-reduction^e

Piedmont

Upper and Middle Coastal Plain

Lower Coastal Plain

Trees 30 ft +  Grass 20 ft ^a

X

X

X^d

85%

Tree buffer ³  20 ft

X

X

X^d

75%

Shrubs buffers ³ 20 ft

X

X^d

75%

Grass buffers ³  30 ft

X

X

X^d

65%

Filter strips ³ 20 ft ^b

X

X

X^d

40%

Nutrient management

X

X

X

Variable

Cover crop

X

X

X

5-15 %

Controlled drainage ^c

X

X

40%

^a The forested area is next to the stream and the grass area away from the stream.

^b Only effective if the drainage area above the filter strip has greater than 1% but less than 10 % slopes.

 Filter strips have to be planted with permanent vegetation (grass, legumes and/or other forbs).

^c Only effective if slope in channel is < 1% and water table can be kept within 36'' of surface soil for 50

   % of field area.

^d Buffers are effective in Lower Coastal Plain but generally are opposed by growers and landowners.

^e Reduction rates based on research and approval of the Neuse Basin Oversight Committee.

Source: Based on decisions by the Neuse River Basin Oversight Committee.