FARM MANAGEMENT OX IRRIGATED FARMS 37 
At least three irrigations are necessary in this area for alfalfa. The 
first comes as soon as the water is turned into the irrigation canal in 
the spring, and the second and third irrigations come immediately 
after the first and second cuttings. If the land is nearly level, the 
furrows are recleaned after each cutting. 
Under existing conditions the increased yields as the result of 
cultivation of alfalfa fields apparently justify the additional expense 
involved. 
A spring-tooth and a spike-tooth harrow are desirable for reno- 
vating alfalfa. The land is first gone over vigorously with the 
spring-tooth harrow, followed by a smoothing over with a spike- 
tooth. Renovating alfalfa is done in the spring after the weeds are 
far enough along to destroy effectively. First-year alfalfa is not 
renovated, as the roots wdl not stand it. 
Seeding alfalfa. — These farmers have a long period in which to 
establish a new field of alfalfa. From the time irrigation water is 
available in the spring until about September 15 is a good time to 
seed. A nurse crop is generally used for spring and fall seeding, but 
late summer seeding is done without a nurse crop. Those who pre- 
fer summer seeding claim that the seed starts quicker, because the 
soil is warmer and fewer weeds are encountered. Considerable 
water however must be available for seeding at this time. On light 
soil inclined to blow, seed is usually sown in the fall, or corn is 
planted in the spring. 
Any of the small grains can be used for a nurse crop, although 
wheat is generally preferred because its value per acre is greater. 
On the lighter soils, where very heavy irrigation is essential to get 
the alfalfa to grow, oats sometimes make a more profitable nurse 
crop because it responds more favorably to the excessive application 
of water. When small grain is used as a nurse crop, about one-third 
less grain is used than when the grain is seeded alone. 
Seeding alfalfa at the rate of 8 to 12 pounds per acre on a well- 
prepared seed bed gives the best results. Most farmers prefer seed- 
ing broadcast. Any of the well-known varieties of seed is satisfac- 
tory. Grimm is hardier, but in this area there is little danger of 
winterkilling; therefore this variety is not grown extensively, as the 
yields are somewhat less than for the other varieties. 
Xew seedings of alfalfa need about twice as much water as older 
alfalfa. It is therefore advisable to plan the new seeding so that it 
will come at a time when the most water can be spared from the 
other crops. 
POTATOES 
Unusually good yields of high-quality potatoes, and in most cases 
satisfactory prices, have made this crop an important source of cash 
income on many farms in the Yakima Valley. Besides fitting well in 
the cropping system, potatoes do not compete seriously with other 
important crops for the farmers' time. (See fig. 12.) On farms of 
less than 80 acres, where not over 10 or 15 acres of potatoes are 
grown, the farmer and his family can do practically all of the work 
until digging. After the other crops are planted in the spring, there 
is plenty of time to plant potatoes, and digging comes after most of 
the other crops are harvested. 
