COMPARISON OF FOREST WITH AGRICULTURAL VALUES 227 



229. Water. In regions of sufficient rainfall, low-lying 

 lands are often swampy. Drainage transforms such soils into 

 permanent agricultural lands of high value. In dry regions, 

 irrigation brings otherwise desert soils under cultivation. Trees 

 ordinarily require fully as much soil moisture as crops. Desert 

 lands are therefore of no value for forestry, but undrained 

 swamp land will produce valuable though slow-growing species. 



230. Personal Factors. The personal element is a large 

 factor in successful agriculture. Experience is the foremost 

 need, but industry, economy and good business capacity are 

 equally helpful. The advancement of agricultural knowledge 

 by experiment stations, and the general trying out of new 

 methods, often make success possible on soils and in climates 

 which were once thought too hostile to permit of agricultural use. 



231. Economic Factors. The development of transporta- 

 tion, and increasing values for farm products, have a stimulating 

 effect on agriculture, and farms can be made to pay in regions 

 near large markets, which would be too poor to cultivate in less 

 accessible localities. This last factor, coupled with the advance 

 in knowledge of farming methods, tends to bring more and more 

 land into agricultural use, and the standard of classification 

 between agriculture and forestry, for this reason, can never be 

 a hard and fast one. 



But the differences between good and poor soil will remain 

 as great as ever and some soil will always be too poor to farm. 

 In densely populated eastern states sandy and rocky land in 

 abundance is found, upon which the inhabitants eke out a mis- 

 erable existence and which no amount of skillful management 

 will make into profitable farms. 



232. Comparison of Agriculture with Forestry as a Source of 

 Livelihood. The use of land for the production of agricultural 

 crops differs in many important particulars from its use for the 

 production of timber crops. Agriculture, the direct source of all 

 food supplies, yields immediate livelihood to the farmer, whose 

 returns are based on an annual cycle. A large element of labor 

 enters into crop production, both for preparing and clearing the 

 soil, and hi actual cultivation and harvesting. Added to this is 



