THE IERIGATION AGE. 



185 



BENEFITS OF TILLAGE. 



Objects of Soil Tillage. 

 Publicity Dept., Deere & Co., Moline, 111. 



Speaking in a broad way, drainage and any 

 similar operation might be included under soil til- 

 lage; but, in the usual acceptance of the term, "soil 

 tillage" refers only to those operations necessary to 

 the preparation of soil for the planting of crops 

 and the processes necessary for bringing these crops 

 to maturity. 



The principal reasons for all care and tillage 

 are : To provide a growing place for desired crop ; 

 to liberate plant food; to conserve soil moisture; 

 and to destroy weeds. 



Tillage Before Plowing. 



It has been proved by experience that very 

 often tilling the ground before plowing is a profit- 

 able practice. 



If land is disced before plowing, the trash is cut 

 up and worked into the soil where it cannot prevent 

 the furrow slice from making a good contact with 

 the subsoil. 



This operation also pulverizes any hard lumps 

 thereby preventing large air spaces being formed 

 at the furrow bottom. These spaces do not promote 

 capillary action. 



Then, besides, discing leaves the soil in good 

 condition to absorb any water that may fall and the 

 mulch formed also prevents to a large degree the 

 escape of moisture already in the soil. 

 Tillage After Plowing. 



After the ground is plowed, it should be disced 

 and harrowed until all lumps are finely pulverized. 

 This is because the delicate plant roots cannot pene- 

 trate hard lumps and are, therefore, deprived of 

 much plant food. 



Another thing, a finely-pulverized soil gives a 

 much greater feeding area for plant roots than a 

 lumpy one. 



Tillage increases the availability of plant food 

 elements by changing the arrangement of soil par- 

 ticles and bringing together those that have not 

 before been in contact. It also changes the relation 

 of the soil with air, water, salts and acids in the soil, 

 making available plant food that would otherwise 

 remain dormant. 



Common-sense tillage will help the productivity 

 of any soil, and in many cases it has made produc- 

 tive supposedly depleted lands. 



Concerning Moisture. 



Soil tillage, in its relation to soil moisture, as- 

 sists in saving a greater portion of the run-off that 

 would otherwise take place with the hard surface 

 of our stubble fields unstirred. It also materially 

 increases the storage capacity of the surface of such 

 fields. 



Tillage assists in the movement of moisture in 

 the soil, by supplying a proper physical condition 

 of soil particles and decaying vegetable matter. 

 With proper tillage, losses from evaporation can 

 largely be prevented. 



Plants require lots of moisture, which must be 

 gotten into the soil and held there till needed. Moist- 

 ure in itself is plant food; but it is also the direct 

 means whereby plants take up other plant foods 

 from the soil. 



An. air-dry soil contains a very slight amount 

 of moisture that has been absorbed from the air, 

 and is known as "hygroscopic water." It cannot 

 contribute to plant growth, and is of only indirect 

 value in the soil. 



Water that stands at a general level in the soil 

 is known as "botton water" when near the surface 

 and surrounding the roots of plants. It excludes air 

 from the soil, and produces an unfavorable condi- 

 tion for crop growth. When it is slightly below the 

 region of root development in the soil, it can be 

 brought to the plant roots by capillarity, and will 

 furnish a good moisture-supply to the crop. 



Capillary water will not move upward through 

 a very loose soil. Neither will it rise above the bot- 

 tom of the furrow unless the contact with the fur- 

 row slice is compact. 



If hard lumps, trash, stubble, cornstalks, etc., 

 are turned under, an insulation is formed at the 

 bottom of the furrow which checks capillary move- 

 ment of water. This is a reason for many crop 

 failures, even when the soil is amply supplied with 

 moisture. 



Discing before plowing prevents such a con- 

 dition. 



On the other hand, stirring the top soil after 

 plowing prevents loss of moisture by evaporation. 



Whenever the surface of the soil is compact 

 as in the case of sod land or cultivated land that has 

 become compact this capillary water rises to the 

 surface, resulting in rapid evaporation of moisture. 



This fact has been proven time and again, both 

 in humid and semi-arid sections. 



The creation of a good earth mulch prevents 

 this loss. 



Therefore, one of the objects of discing, harrow- 

 ing and cultivating is to conserve moisture by mak- 

 ing evaporation more difficult. 



Depth of Tillage. 



Usaully the deeper the cultivation, the more 

 moisture saved. 



It has been demonstrated that a 4-inch mulch 

 saves 72 per cent of the moisture, an 8-inch mulch 

 saves about 88 per cent, and a 10-inch mulch prac- 

 tically checks evaporation. 



Depth of cultivation, of course, depends upon 

 conditions and the crop being grown. 



To get the best results in tilling the soil, as in 

 any other farm operation, good judgment must be 

 used. 



QUINCY VALLEY PROJECT TO COST 

 $40,000,000. 



Plans are being made by the Quincy Valley 

 Water Users' Association to raise $100,000 to com- 

 plete the survey for the irrigation project in Quincy 

 Valley. The bill asking for an appropriation of this 

 amount to carry on the work was recently vetoed 

 by the Governor after it had passed both houses at 

 Olympia. The estimated cost of the project is about 

 $40,000,000. It will open 500,000 acres of irrigated 

 land. The plan is to bring water from Wenatchee 

 Lake in a big ditch, siphon it under the Columbia 

 River, and put it on the broad, level acres of Grant 

 county. 



