SPECIAL FARM TOPICS 289 



more, depending on the slope. With 3-inch contour on land which 

 slopes 8 feet to the mile, the contour lines would be about 160 feet 

 apart. On steeper slopes this space is decreased and the elevation be- 

 tween adjacent contours increased. Land which slopes 50 feet or 

 more to the mile is not suited to check irrigation. The contours may 

 be located by the use of an engineer's level and rod, or by a home- 

 made level. When the contour lines are run the intervening spaces 

 are subdivided into areas containing on an average about three- 

 fourths acre. Provision is also made at this time for field ditches to 

 convey water to each check. After temporary stakes are set to 

 mark the corners of the checks a plow furrow is run around the 

 margin of each so as to mark it permanently. In laying out these, 

 contour lines are run and the rectangular checks are fitted into the 

 spaces in such a way as to require the moving of the least possible 

 volume of earth. Such checks cost more, but they are more con- 

 venient for farming operations. 



Building Levees. In building the levees around checks a 

 scraper drawn by two to three horses or mules is generally used. 

 All knolls and hummocks within the check are first scraped down 

 and the earth placed in the levee. If more dirt is needed, the high 

 corner or end of each check is removed, leaving the floor fairly level, 

 or with a slight grade away from the check box where the water is 

 admitted. The field is then plowed, harrowed, and seeded in the 

 usual way. Levees when first built are too high and steep, but with 

 the subsequent plowing, harrowing, and settling they should be- 

 come satisfactory about the time the first crop of alfalfa is ready to 

 cut. (F. B. 263.) 



The location of laterals w r ill be governed by the character of 

 the soil and the slope of the ground. On light soils a grade of 2 or 

 3 feet per mile should be the maximum. In general, the best re- 

 sults will be obtained if each check is supplied directly from a lat- 

 eral, the lateral being made to form a portion of its boundary. In 

 most cases such an arrangement is possible, and where the expense 

 is not prohibitive this plan should be adopted. In cases where it is 

 necessary to supply one check through another a broad, shallow de- 

 pression across the check through which the water is to be carried 

 will confine the flow of the stream and lead it to the check to be 

 watered, without its spreading over the bottom of the higher check. 

 If this depression be made 10 or 12 feet wide and 4 to 8 inches deep 

 and given just enough slope to drain nicely toward the lower check 

 gate, the crop will cover the sides and bottom of the channel and all 

 implements will cross it without inconvenience. 



No exact estimate can be given of the expense of checking, as 

 the price will vary with the character of the land and also the lo- 

 cality. For contour checks the cost of building levees, leveling the 

 checks, and constructing laterals averages about $7 or $8 per acre 

 on ordinary land, including surveying at 20 to 30 cents per acre. 

 Check boxes at $1 to $5 per acre would bring the total expense up 

 to $8 to $13 per acre. In building rectangular checks on uniformly 

 sloping land, one man with four horses and a scraper can check 



