Which of the Following Is Not a Characteristic of Alley

Which of the following is not a characteristic of alley cropping systems that are being studied as one alternative to slash-and-burn systems?

A) Food crops are grown in alleys with borders provided by woody species.
B) Nutrients accumulated from subsurface soil layers by the border plants are added in residues to the surface of the cropped areas.
C) The woody border plants help conserve water in the cropped alleys by shading the soil.
D) Organic mulch cut from border plants helps control weeds and prevents runoff and erosion.
E) crop yields in humid regions have generally been satisfactory using this system