Rhubarb Triangle
The Rhubarb Triangle is a 9-square-mile (23 km2) triangle in West Yorkshire, England between Wakefield, Morley and Rothwell famous for producing early forced rhubarb. It includes Kirkhamgate, East Ardsley, Stanley, Lofthouse and Carlton. The Rhubarb Triangle was originally much bigger, covering an area between Leeds, Bradford and Wakefield. From the first decade of the 20th century to 1939 the rhubarb industry expanded and at its peak covered an area of about 30 square miles (78 km2).
Rhubarb is a native of Siberia and thrives in the wet cold winters in Yorkshire. West Yorkshire once produced 90% of the world's winter forced rhubarb from the forcing sheds that were common across the fields there.
In February 2010, Yorkshire Forced Rhubarb was awarded Protected Designation of Origin (PDO) status by the European Commission’s Protected Food Name scheme after being recommended by Department for Environment, Food and Rural Affairs (Defra).
The cultivation method for forced rhubarb was developed in the early 1800s. The fields were fertilised with large quantities of horse manure and 'night soil' from the nearby urban areas and woollen waste from "mungo and shoddy" mills.
The rhubarb plants spend two years out in the fields without being harvested. While in the fields the plants store energy from the sun in their roots as carbohydrates. The roots are subjected to frost before being moved into sheds in November where they are kept in complete darkness. In the sheds the plants begin to grow in the warmth and the stored carbohydrate in the roots is transformed into glucose resulting in forced rhubarb's sour-sweet flavour. The sheds are long low buildings which are heated; originally with coal, which was plentiful and relatively cheap in the area but has been replaced by diesel.
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