1. The Northern forest was long the chief source of the coniferous lumber production in the United States. The principal timber tree of this region is the white pine, usually known in Europe as the Weymouth pine. It has an average height when mature of 110 ft., with a diameter a little less than 3 ft., but the virgin timber is approaching exhaustion. White pine was one of the first trees to be cut extensively in the United States, and Maine, the pine tree state, was at first the centre of production. In 1851 the cut of white pine on the Penobscot river was 144 million ft., that of spruce 14 million and of hemlock 11 million. Thirty years later the pine cut had sunk to 23 million, spruce had risen to 118 million, and hemlock had passed pine by a million feet. Meanwhile, the centre of production had passed from the north woods to the Lake States, and for many years this region was the scene of the most vigorous lumbering activity in the world. The following figures show the cut for the Lake States from 1873 to 1906. It is certain that the remarkable decline in the cut of white pine which these figures show will continue still farther. 1873 3,993,780,000 | 1890 8,597,659,352 1874 3,751,306,000 | 1891 7,879,948,349 1875 3,968,553,000 | 1892 8,594,222,802 1876 3,879,046,000 | 1893 7,326,263,782 1877 3,595,333,496 | 1894 6,821,516,412 1878 3,629,472,759 | 1895 7,050,669,235 1879 4,806,943,000 | 1896 5,725,763,035 1880 5,651,295,000 | 1897 6,233,454,000 1881 6,768,856,749 | 1898 6,155,300,000 1882 7,552,150,744 | 1899 6,056,508,000 1883 7,624,789,786 | 1900 5,485,261,000 1884 7,935,033,054 | 1901 5,336,000,000 1885 7,053,094,555 | 1902 5,294,000,000 1886 7,425,368,443 | 1903 4,792,000,000 1887 7,757,916,784 | 1904 4,220,000,000 1888 8,388,716,460 | 1905 3,777,000,000 1889 8,183,050,755 | 1906 3,032,000,000 Second to the white pine among the coniferous lumber trees of the Northern forest is the hemlock (_Tsuga canadensis_). It is used chiefly for construction purposes and furnishes a comparatively low grade of lumber. The spruce (_Picea rubens_) is used chiefly for lumber, but it is in large and increasing demand in the manufacture of paper pulp. For the latter purpose hemlock, poplar (_Populus tremuloides_ and _P. grandidentata_) and several other woods are also employed, but on a smaller scale. The total consumption of wood for paper in the United States for 1906 was 3,660,000 cords, of which 2,500,000 was spruce. Of this, however, 720,000 cords were imported from Canada.