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After three or four years, this fold would be ploughed up by exceedingly rude instruments. Barley or certain kinds of wheat would be grown year after year until the crop was not worth gathering. When that happened, another fold would be ploughed up. Probably the whole of Pennell Brae went through this rude sort of agricultural treatment at one time or another. At the same time goats, cattle, and the demand for firewood, obtained in the most reckless and wasteful manner, would have very seriously interfered with the forest.