Irrigated Agriculture in the San I^uis Valley 25 
On very heavy lands it is sometimes not advisable to use the press 
wheels, but cover with chains or other devices. Under other con¬ 
ditions the press drill is to be preferred. 
Spring Wheat .—Practically all of the spring wheat grown 
has been Defiance. The famous Marcjuis wheat has been tested. 
This variety matures in a season from ten days to two weeks earlier 
than Defiance and has a better quality of grain, but under good 
cultural conditions does not yield nearly so heavy a crop, conse- 
cjuently, for most conditions Defiance is the preferred variety. 
Spring wheat should follow peas, or cultivated crop in the 
rotation. Where the soil moisture is such as to permit fall plow¬ 
ing without undue blowing by winds during the winters the land 
should be fall plowed so that early spring seeding may be done. 
Seeding should take place quite early in the spring, in March and 
April, if possible, injury by early frosts being little to be feared. 
Preparation of Soil .—Land for wheat should be plowed rather 
deeply a considerable time previous to planting. Fall plowing ac¬ 
complishes this for spring wheat, altho following dry winters 
land fall plowed may be rather dry for seeding in the spring. This 
is really the only objection that can be offered where winds do' not 
need to be considered with a specific soil. Prior to seeding, land 
should be well compacted by disking and harrowing so as to pro¬ 
vide a firm seed bed. The preparation of land for wheat, oats, 
barley, spring emmer and other spring small grain crops should be 
much the same. Spring wheat should be seeded at the rate of 
about ninety pounds per acre for most irrigated conditions of the 
valley. If a smaller amount is used, the stand will be so thin that 
weeds will take partial possession; if more is used, the stand will 
be so thick that the grain itself will act as a weed and reduces the 
yield by undue competition. 
In general the care of seed thruout the valley is extremely 
lax. Seed is often mixed with barley, oats, peas, wild peas and 
other impurities. More care directed to screening and grading the 
seed would result in much more satisfactory crops. 
Irrigation .—In the spring if the ground holds moisture enough 
to keep wheat growing, it should not be irrigated. An irrigation 
should be given, however, just as soon as water is needed. In 
other words, the wheat should be kept growing continuously. Irri¬ 
gation should stop at the blooming period and in no case should 
water be applied after the grain has reached the soft dough stage, 
except on almost pure gravel patches. Late irrigation deteriorates 
the quality of the grain and prevents proper ripening. 
