Natural  farming  
A system of agricultural  devised by Masanobu Fukuoka that seeks to follow Nature by minimizing human  interference: no chemical cultivation, no synthetic fertilizers or prepared compost,  no weeding by tillage or herbicides, no dependence on chemicals.
  
  Neutrophiles  
  
 
  The plants which can  grow in neutral soils (pH range 6.5 – 7.4).
Net farm income 
 
The  money and non-money income form operators realize from farming as a return for  labor, investment, and management after production expenses have been paid. Net  farm income is measure in two ways net farm income before inventory adjustment  and net farm income after inventory adjustment. Net farm income doesn't include  changes in the value of inventories such as crops and livestock at the end of  the year. 
Noxious  Weed   
 
A weed plant especially  undesirable, troublesome and difficult to control, e.g., Cynodon  dactylon, Cyperus rotundus,  Sorghum halepense, etc.
Nurse Crop 
 
A  companion crop which nourishes the main crop by way of nitrogen fixation and/or  adding the organic matter into the soil, e.g., cowpea intercropped with cereals  or new plantations of fruit trees.