SUGGESTIONS TO SETTLERS IN COLUMBIA RIVER VALLEY. 9 



There slioukl be a hole for each lurrow, because it requires too mucli 

 attention to (Uvide a stream and divert the water into two or three 

 furrows. The size of the stream to run in the furrows depends upon 

 tlie character of the soil and the grade of the furrow. Generally 

 speaking, the coarser tlie soil and the steeper the grade the smaller 

 should be the stream. When first beginning to irrigate, it is best 

 to turn on all of the water that the furrow will carry witliout washing 

 too }>adly, in order to get the entire length of the fin-row wet as 

 (quickly as possible. The stream may then be reduced until there 

 will be no waste of water at the end of the furrow. While a small 

 stream will usually give tlie best results, the irrigator must learn 

 from experience the size most satisfactory^ for his conditions. The 

 aim should be to apply the water as cjuickly as possible, get the 

 ground evenly moistened, and prevent the washing of the soil in 

 the furrows and the loss of water by seepage. 



WHEN TO IRRIGATE. 



Irrigation in the Columhia River Valley should begin about April 

 1, and for most crops on sandy soil frecjuent applications are necessary 

 during the growing season. Every two weeks is perhaps none too 

 often to irrigate orchards, alfalfa, and clover. When a field is being 

 seeded to alfalfa or clover it is necessary to keep the soil moistened 

 at all times until the crop is well established. Garden crops may 

 require water every week or oftener. During the picking season 

 strawberries are usually watered every day, or every other day at 

 least. After the crop is removed they receive only enough water to 

 keep the vines alive. 



The irrigation of the orchard in the late fall keeps up the growth 

 of the trees too long and subjects them to the danger of winter- 

 killing. As a rule no water should be applied after September 15. 

 Growth will then be checked early enough for the wood to harden 

 before winter. 



In the spring of the year when strawberries are in bloom and liable 

 to injury from frost, the danger may be lessened by running water 

 between the rows. Experience has shown that the loss from frost 

 is much less where the ground is kept moist by irrigation than it is 

 on dry ground, provided the temperature is but a few degrees below 

 freezing for a short period only, 



QUANTITY OF WATER TO USE. 



With a deep soil and subsoil, Jieavy but infrequent irrigation is 



recommended. But in a region like the Colum])ia Kiver Valley, 



with soil and subsoil generally of low water-holding capacity, fre- 



(|uent light applications of water must necessarily be the rule. 



38844— Cir. 60—10 2 



