Residue Burning was banned in 5 states by the agency

Crop residue in the field after harvesting is burnt to prepare land for the next cultivation. It is the most inexpensive and effective method to remove excess residue to facilitate timely planting and also to control pests and weeds.
But the burning of crop residue is banned in 5 neighboring states of Delhi-NCR by agency National Green Tribunal in an order passed on 10^th December 2015 directed and prohibited agricultural residue burning in any parts of Delhi, Rajasthan, Haryana, Punjab, and Uttar Pradesh to avoid air pollution in the city.