Southdown sheep no longer economical and smaller flocks averaged only 135 ewes apiece. The use of artificial fertilizers had gained ground, and the combine-drill, which sowed grain seeds and fertilizer together, rendered close-folding by sheep unnecessary. Gradually surrendering to basic arable farming changes, the Southdown became largely a grassland breed. During the interwar years, the United Kingdom was known for farm animal breeding, and pedigreed Southdowns were still being exported to most parts of the world, especially New Zealand. In 1937, the number of exported Southdowns reached 459 head. During the Great Depression, a severe and prolonged fall in the prices of
Norfolk Horn but dry environments. The breed is long-legged with black faces and legs. Both sexes have horns, although these are larger in the males. At maturity, an ewe weighs about . The breed is described as "flighty" and is likened to goats in their ability to jump over obstacles such as fencing. It was a popular breed in Norfolk until the middle 19th century, when "improved" breeds such as the Leicester and Southdown appeared. Norfolk Horn ewes were mated to Southdown rams to produce high quality meat-producing lambs, and this cross became established as a separate breed, the Suffolk. The Norfolk