THE IRRIGATION AGE. 



273 



DRAINAGE NEEDED FOR IRRIGATED LANDS 



MORE than ten per cent of the irrigated lands in 

 the United States which have had water for 

 any considerable period of time are now either ab- 

 solutely unproductive or given over to poor pastures 

 and unprofitable crops, according to the United 

 States Department of Agriculture. Waterlogging 

 and the accumulation of harmful mineral salts are 

 responsible. Even in some of the most recent irri- 

 gation projects serious injury from these causes has 

 been wrought. 



Methods of reclaiming land which has fallen 

 into this condition forms the subject of a new bul- 

 letin of the Department (No. 190), "The Drainage 

 of Irrigated Land." Drainage supplemented by 

 proper methods of cultivation, cropping, and irri- 

 gation, will restore these waterlogged areas to a 

 condition in which they can be farmed with profit. 

 Proper drainage will accomplish four objects: 



(1) The lowering of the ground-water table to 

 a depth where the moisture and air within the root 

 zone will be properly balanced. 



(2) The creation of an outlet for percolating 

 water, so that the ground-water table will not fluc- 

 tuate excessively. 



(3) The rapid removal of excess moisture fol- 

 lowing spring thaws. 



(4) The creation of an outlet for the down- 

 ward moving water used to dissolve out the in- 

 jurious salts. 



Incrustations of alkali salts and the presence 

 of highly alkali-resistant plants are frequently indi- 

 cations of overirrigation. In some cases ponds, 

 bogs, and marshes are also found, but in others 

 there are no visible signs of excessive wetness and 

 its existence can only be inferred from its effects 

 upon vegetation. Thorough knowledge of under- 

 ground conditions is necessary. 



To drain irrigated areas will cost, it is esti- 



mated, on the average farm from $10 to $20 an acre 

 except under unusual conditions, when the cost may 

 run as high as $50 an acre. Both open canals and 

 covered conduits are in general use. The open 

 canals, however, are intended primarily for the main 

 outlet systems in which provision must be made 

 for a considerable flow of water. The covered drains 

 are for farm drainage proper, although, except for 

 the additional expense, they could be used equally 

 well for the main outlets. As a matter of fact, al- 

 though they cost more than the open canals, the 

 maintenance charges are usually lower, much valu- 

 able space is saved, and cultivation and irrigation 

 are much easier with them than with open canals. 

 Where covered conduits are employed they are 

 usually made either of cement or clay tile. In some 

 localities lumber box drains are used, but this is 

 usually advantageous only in isolated places where 

 lumber is cheap and transportation rates high. The 

 life of such a drain is reasonably long if the lumber 

 is. continuously wet, but if alternate wetting and 

 drying takes place, the material may last only a few 

 years. 



In properly drained land bacterial activity is in- 

 creased and more plant food provided by the admis- 

 sion of air into the soil to take the place of the ex- 

 cess water which has been removed. The downward 

 movement of water through the soil also leaches out 

 the excess of harmful salts, and this is one of the 

 most important functions of drainage in the irri- 

 gated sections. The water removed by the drainage 

 system may be employed for the irrigation of other 

 areas, thereby increasing the available irrigated 

 area. Furthermore, drained land may be plowed 

 earlier than undrained, and in consequence may be 

 irrigated earlier. This is an obvious advantage in 

 that it makes it possible for the land to be irrigated 

 before the supply of water becomes reduced. 



IS YOUR FARM PAYING YOU WAGES? 



By E. H. THOMPSON 



U. S. Department of Agriculture, Bureau at Plant Industry. Office of Farm Management 



A CAREFUL study in regard to the profits made 

 by a large number of farmers in different parts 

 of the United States shows that the size of the farm 

 business is one of the most important factors con- 

 trolling the farmer's income. The problem of how 

 large an investment is needed in order to carry on 

 a certain type of farming to advantage is of the 

 utmost importance. The amount of this investment 

 will vary according to the type of farming and to 

 the region selected. 



In a survey of more than 100 farms in an irri- 

 gated district in Utah only three farm owners with 

 less than $10,000 total capital received a labor in- 

 come of more than $1,000 for their year's work. In 

 a group of 35 of these men, who had small farms 

 and an average capital of $5,345, the average labor 



income was $235. One out of every five received 

 nothing for his labor and made less than 5 per cent 

 interest on his farm investment. With high-priced 

 land this amount of capital gave him too small an 

 area to utilize to advantage. If land were cheaper, 

 so that a much larger area could be obtained with 

 this same amount of money, then $10,000 might be 

 sufficient investment to give the farmer a substan- 

 tial income. 



In the Central States, where corn, wheat, and 

 oats are the prevailing crops and where land is from 

 $150 to $250 an acre, $10,000 would be entirely too 

 small an investment to yield the owner a good in- 

 come, for the reason that 40 to 50 acres, the total 

 amount of land he could possibly buy with this 

 amount of money, would not utilize his teams, ma- 

 chinery, or labor to the fullest advantage. 



On the other hand, the number of acres is not 



