166 A NATIONAL PLAN FOR AMERICAN FORESTRY 



Agricultural shifts have constituted the most influential factor in 

 effecting the abandonment of land for agriculture. It is possible that 

 during the coming decade mechanization of agriculture and exodus 

 of farm population to cities may not operate to bring about farm 

 abandonment to the extent that they did from 1920 to 1930. The 

 facts that population probably will not increase so rapidly as in the 

 past decade and that exports do not promise to expand rapidly may 

 make the pressure of competition of lower-cost areas on higher-cost 

 areas more severe. Increased efficiency in production through better 

 livestock, better crops, greater use of fertilizer, etc., may also intensify 

 interregional competition. Erosion, unless checked, will probably 

 also bring about more and more abandonment. 



AGRICULTURAL LAND AVAILABLE AND TO BE AVAIL- 

 ABLE FOR REFORESTATION IN THE ORIGINALLY 

 FORESTED REGIONS EAST OF THE GREAT PLAINS 



Any estimate of the amount of agricultural land available for re- 

 forestation can be only a very rough approximation. The previous 

 discussion has shown that many factors have and will influence the 

 amount of agricultural land available for reforestation. Data are 

 not available to show how much agricultural land was abandoned 

 prior to 1910, but in the discussion of land abandonment it was 

 estimated that over 30,000,000 acres of land have gone out of agri- 

 cultural production since 1910 in the originally forested regions east 

 of the Great Plains. Some of this land has been put to residential 

 or other intensive use, some has already grown up to forest; the 

 remainder is largely idle and available for reforestation. There is 

 considerable variation in the quality of this land for forestry pro- 

 duction, and this variation would be considered in determining a 

 forestry program for such land. 



In addition to this abandoned agricultural land, 21,500,000 acres 

 of land were designated as idle or fallow crop land still in operated 

 farms, in 1930, in these regions. (See table 6.) Much of this land 

 is in the first stage of abandonment and is largely available for con- 

 sideration in the development of a forestry program. 



A third class of land which contains a considerable area that might 

 be available for reforestation is that reported by the census as "pas- 

 ture other than plowable or woodland pasture". In 1929 there were 

 29,500,000 acres of such land in farms in the forest regions. (See 

 table 6.) Much of this is in an advanced stage of abandonment, 

 although still being utilized to some extent in agricultural production. 



Natural reforestation of land comes about rather slowly. It is 

 probable that little of the land abandoned since 1920 has been re- 

 forested and that much of the land abandoned between 1910 to 1920 

 is available for reforestation as well as some of the land abandoned 

 prior to 1910. Although it is impossible, in the absence of actual 

 surveys, to determine the extent of agricultural land available for 

 reforestation, it seems reasonable to assume that most of the land 

 abandoned since 1920 and perhaps half of that abandoned between 

 1910 and 1920 might be considered available for this purpose. If, 

 in addition, half the idle crop land is added and half the pasture not 

 already in woods or not plowable, there is a total of over 50,000,000 

 acres of agricultural land that might be available for some type of 



