TWIN TREES AND NATURAL GRAFTS 



611 



taken by inexperienced observers for upright forks. These 

 "identical twins," to borrow a term from the medical 

 profession, for the sake of distinction, differ from those 

 just described in being of the same age and parentage, 

 and the two forks into which they sooner or later diverge 

 are generally of the same size and vigor, while in the 

 "mixed twins" of different stocks, they vary according 

 to the relative ages and growth rate of the parent spe- 

 cies. 



Twin and composite stems of various kinds arealso 

 often produced by the union of root sprouts that spring 

 up around the stumps of dead trees, or if the stump is too 



large for the growing sprouts to be brought into con 

 stact, a root colony, such as that shown in the illustra- 

 tion, (Fig 5), may result. And sometimes, when the main 

 axis of a seedling is broken at an early stage of growth, 

 the two strongest branches remaining are apt to take an 

 upright direction, thus simulating a twin or a double 

 stem so closely that it is not easy to distinguish between 

 them. In general, the true twins are distinguished by a 

 suture which follows their line of union down to or near 

 to the ground (Fig. 1), or in some cases, by a protrusion 

 on opposite sides of the common trunk (Fig. 7), as if the 

 coalescing stems had been forced by their increasing size 

 to bulge out at right angles to the line of pressure. 



THE FUTURE OF THE AMERICAN LUMBER SUPPLY 



By A. B. Recknagel 



[Professor of Forest Management and Utilization, Cornell University ] 



'T'HE subject of the future of the American Lumber 

 Supply is a large subject and can best be approached 

 by a study of the past developments of the industry, its 

 present resources and then, predicated upon these two. 

 a look into the future may be ventured. 



In 1850 the United States produced five billion board 

 feet of lumber with New York leading, Pennsylvania 

 second, Maine third, Ohio fourth, Indiana fifth and 

 Michigan sixth. 



In i860 the total production was eight billion feet. 

 Pennsylvania led with New York, Michigan, Maine, 

 Ohio, Indiana and Wisconsin following in the order 

 named. 



In 1870 the production had risen to 12,755,000,000 

 feet and Michigan topped the list with Pennsylvania, 

 New York, Wisconsin, Indiana, Maine, Ohio and Mis- 

 souri next in rank. The center of production definitely 

 passed in this decade to the Lake States where it re- 

 mained for thirty years. Michigan led the other states 

 of the Union from 1870 till 1900 when Wisconsin took 

 the lead till 1905. 



About 1895 began the rise of Louisiana, Mississippi 

 and the other Southern States in the list of lumber pro- 

 ducers. Thus Louisiana was third in 1895, second in 

 1910 and first in 1914. The Southern Pine region over- 

 topped the Lake States in 1900 and was pre-eminent until 

 1920 when for the first time the State of Oregon dis- 

 placed Louisiana from second rank. Southern pine may 

 be expected to recover part of the lost ground in the 

 next few years, but the indications are that the suprem- 

 acy in lumber production is moving to the West. 



The shifting of the lumber production center from the 

 south to the west coast began with the rise of the State 

 of Washington to a leading place. Since 1905, with the 

 single exception of the year 1914, the State of Wash- 

 ington has held supremacy as a lumber producer. Today 

 (1920) out of a total cut of 33,798,800,000 board feet, the 



order of the first twelve states is: Washington, Oregon, 

 Louisiana, Mississippi, California, Arkansas, Alabama, 

 Texas, North Carolina, Wisconsin, Virginia and Flor- 

 ida. All the rest produce less than a billion feet yearly. 



The curve of lumber production from 1904 on 

 indicates a steady diminution since 1912 and a high point 

 in 1906 and 1907. In 1919 the cut was 34,552,076,000 

 board feet and in 1920 the cut was 33,798,800,000 board 

 feet. The cut for 1921 has not yet been computed. 



The statistics compiled by the United States Forest 

 Service in 1920 show that the standing saw-timber in 

 the United States aggregates 2,214,893,000,000 board feet 

 of which nearly half or 1,141,031,000,000 board feet are 

 on the Pacific Coast and of this half nearly one half or 

 558,571,000,000 feet is Douglas fir. 



In all the Eastern States there are only 850,721,000,000 

 board feet and in the Rocky Mountains 223,141,000,000 

 board feet. 



The Pacific Coast in the saddle and Douglas fir alone 

 could support the present cut of 7,000,000,000 feet of that 

 species for 80 years were it not for the inevitable in- 

 crease of the amount cut due to failing supplies of other 

 species. A drop in the production since 1919 of 15 per 

 cent in yellow pine. 13 per cent in white pine, and 16 per 

 cent in spruce, indicates the drain there will be on the 

 remaining supply of Douglas fir. 



Ultimately the question is not where is the most of the 

 remaining virgin timber but where is the most produc- 

 tive forest area? as the American Forestry Association 

 points out. When our virgin timber is gone we will 

 have to "grow our own" since it is obviously out of the 

 question to depend upon foreign sources of supply. The 

 situation in this respect reveals a present forest area of 

 463,461,000 acres in the United States (excluding Alas- 

 ka) which figures out 4.32 acres of forest land for each 

 inhabitant. 



