Wheat is the main UK arable grain crop with around 2,000,000 hectares grown, 25% of which is exported. It has a value of about £1.2 billion although the price is variable and is currently average at about £140 per tonne. Average yield is about 8 tonnes per hectare. In the UK the climate has always been well suited to the production of wheat and even 1,000 years before the Romans arrived, farmers were exporting surplus grain to Europe. Winter wheat gives a higher yield due to the longer growing season but has worse weed problems than spring wheat. Farmers have traditionally grown wheats for a number of different markets. Hard wheats (high protein and starchy gluten) are sold for the production of bread. Soft wheats (low protein and weak gluten) are sold for biscuits and other general flour uses while lower quality wheats are used in animal feed rations.