PLANTING ON CONTOUR DITCHES 



51 



Spirit level on frame, to make easy the laying out of 

 contour irrigation. 



Permanent Ditches. The use of permanent ditches was for- 

 merly very common in the irrigation of sloping garden ground and 

 is still somewhat observed. These ditches are drawn very nearly 

 on contour lines, only just enough fall being given to move the 

 water slowly. When the slope is nearly uniform the ditches are 

 almost parallel and they are distanced according to what is known 

 of the movement of water by seepage down the slope in each par- 

 ticular soil. The plantings are made on the plan of each strip 

 securing its moisture from the ditch above and water is admitted 

 occasionally or kept running almost continuously according to the 

 needs of the particular crop or the leakiness of the ditch. The out- 

 flow from the ditch, after traversing backward and forward its full 

 length, is carried to an alfalfa patch below and thus utilized. These 

 permanent ditches serve a good purpose in saving hillsides from 

 washing as they catch the surface storm water before it has a chance 

 to acquire much headway and carry it down gently. Where the 

 soil favors such distribution very good results are attained with 

 these ditches, but the tendency is to use the ditches too long and 

 allow them to become cemented by action of water and deposit of 

 slime. Besides they grow weeds and distribute seeds if their banks 

 are neglected. 



Small Zigzag Method on a Slope. Contour ditches for single 

 rows of vegetables have satisfied H. L. Wolfsen of Colfax, Placer 

 county, who gives this advice : 



After the soil is prepared, stakes should be placed where the contour 

 ditch will be made. To do this, a carpenter's level is fastened to a board 

 which has two legs of equal length. A half-inch is then added to the foot 

 of one leg which will insure the right amount of fall to the ditch. 



Contour so as to wind back and forth down the slope. It will depend 

 upon the kind of vegetables grown how far the ditches should be apart. At 

 the turns, which will be quite steep, stones may be placed to prevent washing. 

 The ditches should not be more than twenty or thirty feet long before they 

 turn, or else the rows will be too far apart. The amount of water to irri- 

 gate with will determine how far the patch should extend. 



When the ditch is being made, scrape the upper edge smooth, placing 

 all of the soil which is taken out on the lower side and smoothing it, ready 

 for the seeds, or young plants from the hot-beds. Water should be run in 

 the ditch in a moderately large stream at first until it reaches the end of the 

 ditch, and then in a small stream until the moisture shows past the seed row 

 or small plants. Then the water can be stopped and at the proper time 

 cultivate the lower side of the ditch with a rake. The top of the rows will 



