14 CULTIVATED FORAGE CROPS OF THE NORTHWEST. 
THE ‘“S‘ INLAND EMPIRE.” 
This region, sometimes known as the Palouse country, comprises 
eastern Washington, northeastern Oregon, and northern Idaho. It is 
characterized by a dark, fine-grained basaltic soil of great fertility and 
of very uniform character over a wide area. The limiting factors of 
agriculture here are rainfall and altitude. With Pasco, Wash., as a 
- center, where the annual rainfall is about 6 inches, the rainfall increases 
in all directions, attaining a maximum of about 30 inches at the base of 
the Blue and Rocky mountains on the east, and the Cascade Mountains 
on the west. A considerable portion of this area in Washington and a 
smaller section in Oregon have a rainfall of less than 10 inches. In 
this portion irrigation is practiced. In Washington, about 150,000 
acres are under irrigation within this area, alfalfa being the staple hay 
crop, with a yield of 3 to 8 tons of hay per acre, at three cuttings. 
The principal irrigated areas are situated in Yakima, Kittitas, Walla 
Walla, and Chelan counties, Wash. Smaller areas, especially in narrow 
canyons along the smaller streams, are located in various parts of 
Oregon and Washington. The Kittitas Valley in Washington, which 
lies at a higher altitude (about 1,600 feet) than any other considerable 
irrigated area in the region in question, grows alfalfa, timothy, and 
clover, producing hay of excellent quality. Like all other regions 
between the Cascades and the Rockies, the haying season is free from 
rain, which fact accounts for the excellent quality of hay produced. 
Those portions of the ** Inland Empire” having more than 10 inches 
of rainfall have heretofore been devoted almost exclusively to wheat 
growing. In recent years considerable attention has been given to 
hay and pasture grasses. Brome grass (Bromus inermis Li.) has 
proven to be an excellent pasture grass in this region. It also yields 
profitable crops of hay the second and third years after sowing. A 
superior quality of brome grass seed is produced here. Of the hay 
grasses, timothy and red clover are preferred for lowlands and 
alfalfa, red clover, and orchard grass for uplands. On these wheat 
lands, which he at an altitude of 1,500 to 3,000 feet, alfalfa produces 
one or two crops a year, and is rapidly becoming an important hay 
crop. Irrigation is not practiced in this region where the rainfall 
exceeds 10 or 12 inches a year. 
Heretofore, and even at the present time, the principal hay of the 
wheat-growing area has been a mixture of wheat and wild oats (Avena 
Jatua). Where the rainfall exceeds 18 inches wild oats are trouble- 
some in the wheat fields, particularly on north hillsides, where snow 
banks protect them against freezing. Hay is cut from those patches 
in the wheat fields where wild oats predominate. When cut green 
this hay is of good quality, but many careless farmers cut it so late 
that the seeds are mature, and the hay is not only of poor quality but 
