98 A NATIONAL PLAN FOR AMERICAN FORESTRY 



chased lumber, posts, firewood, etc., at an aggregate cost of $167,- 

 000,000. The actual cash outlay for these materials was more than 

 three fourths of the expenditure for fertilizers reported by 2,200,000 

 farmers. An adequate supply of a variety of forest products at low 

 cost is vitally essential for the agricultural prosperity of most parts 

 of the country. 



AGRICULTURE IN MANY REGIONS DEPENDS ON ADEQUATE 



SUPPLY OF WATER 



Besides their function as suppliers of raw materials, forests in 

 many regions, particularly in the West, serve agriculture through 

 their influence on water supplies. Without dependable supplies of 

 water it would be impossible successfully to cultivate the 19 million 

 acres of irrigated land. In the 11 Western States more than 240,000 

 farms, or almost half of the total number, depend on irrigation water. 

 Approximately 17,500,000 acres are irrigated in these States. The 

 total value of these irrigated farms in 1930 was $4,500,000,000 and 

 more than $900,000,000 has been invested in the irrigation works. A 

 large proportion of the water used in irrigation originates on forest 

 land. Without the forest cover, the flow of water would become less 

 regular, larger and more costly storage reservoirs would be necessary, 

 and great expense would be entailed in removing silt from the reser- 

 voirs and ditches and, in many instances, in rebuilding dams. 



FORESTS PROTECT FARMS AGAINST DAMAGE FROM EROSION 



Another way in which forests serve agriculture is by holding in 

 place the soil on slopes and along the banks of streams. Many 

 thousands of acres of rich agricultural bottom-land, in the East as 

 well as in the West, have been ruined by the deposition of silt, sand, 

 gravel and boulders which were washed down from the hillsides after 

 the forests were destroyed. Hundreds of thousands of acres have 

 been cut to pieces by deep gullies which could have been prevented 

 by preserving the forest cover at the critical points. The influence 

 of forests in relation to water supplies and erosion is discussed in 

 detail elsewhere in this report. 



FORESTS FURNISH SUPPLEMENTARY INCOME TO FARMERS 



Combined agriculture and forest work afford a livelihood to hun- 

 dreds of thousands of farmers who would find it difficult to make a 

 living from farming alone. This is particularly true in localities 

 where the land suitable for cultivation constitutes a relatively small 

 proportion of the total area or is of low productivity. These condi- 

 tions are common throughout the inhabited hill and mountain regions, 

 and also in the more level, sandy portions of the Lake States and the 

 Southeast. The forests enable the farmers to employ themselves and 

 their teams and other equipment profitably during the winter or 

 other seasons when farm work is slack. They may either work in 

 their own woods, getting out timber for home use or for sale, or they 

 may work for wages in logging camps or mills. In 1929, forest 

 products to the value of $240,000,000 were cut from 2,500,000 farms. 

 From one third to one half of this sum represents cash income for 

 materials sold. In 1919, forest products worth $394,000,000, of which 

 $217,000,000 worth were sold, were cut from 1,800,000 farms. 



