Sugar beet is an important crop of arable rotations, grown in conjunction with wheat, barley or pulses. It is a break crop, (one that improves the soil by returning organic matter and preventing the build up of disease). It is sown from early March to April and harvested before the onset of winter frosts, between September and Christmas when the its sugar content is highest. It is mainly grown in the East of England, from Yorkshire to Essex, and in the West Midlands. The sugar content of the root is around 17%. It provides over 50% of UK sugar. Around 170,000 hectares are grown, producing 1.4 million tonnes of sugar and 750,000 tonnes of animal feed.