Level and remove animal and livestock poaching from your pasture.
This is usually done in early spring as soon as the ground conditions allow and there are two main reasons for rolling your pasture. 

The first is to remove any ruts, wheel marks, hoof prints or poaching caused by machinery or livestock when the ground conditions are soft in the autumn/winter period. This will give you a clean start with a nice level pasture for the year ahead.

The second reason for rolling is if you are planning on making hay, silage or haylage in the field. By rolling it in the spring before the grass gets too long you flatten any mole hills that have been created over the past year. This is important as you don’t want the mower to mix the soil in with the grass at the time of cutting as this will contaminate the crop and animals will not eat it.