There are three principal types of thatch in the United Kingdom. These are “water reed”, “combed wheat reed” and “long straw”. The first is based on the water reed Phragmites australis and the latter two are based on cereal straw: wheat, rye or a cross between the two, Triticale. The term “Norfolk reed” is used for water reed roofs thatched with material obtained from Norfolk reed beds. Combed wheat reed is sometimes called “Devon reed”, but despite this name it is not true reed but is wheat straw, laid butts down on the roof.
Combed wheat reed and long straw roofs differ in appearance because of the treatment of the straw and the way it is placed on the roof. Long straw evolved as a means of thatching with cereal straw that had been processed through a threshing drum and had become “bent, broken and jumbled”. It was often wetted to facilitate its handling and is laid on the roof with a mixture of butts and heads at the surface. The result of this is that a greater length of the stem is visible at the surface and this is why the term “long straw” arose. It does not relate to the length of the stems in use.