Mountain Home maverick. [volume] (Mountain Home, Idaho) 1906-1911, 1910-04-07

fBy Samuel Fortier. Chief of irriga-
tions, u S. Department OF
Agriculturel

alfalfa differ widely because of diver
sity of soils and subsoils. in climate
and topography, in the nature of the
water supply, the size Of the farm,
the amount of money available for
pfeparing the land for water, the
prevailing crops grown and the early
training and environment of the ir-
rigator The standard methods have
been grouped under the following
heads, namely, the border method,
the check method flooding from field
Iaterals. furrow irrigation and other
less comon methods, with various
notifications of each.
IN passing, it may be said that the
usual order is to locate and build
the farm bitches first and prepare
the land afterwards In this bulletin
it has been deemed best to describe
the methods in use and then con-
slider the location and construction
of farm bitches. After one has a
general knowledge of the various
ways of applying water and of the
size and character of the bitches re-
quired for each method he is in a
better position to understand the
proper methods to adopt in building
farm bitches. This subject will,
therefore, be treated separately
under its own heading.
Essentially the border method con-
sists of the division of field or
tract into long, narrow strips or
lands by low. fiat levees. which
usually extend in the direction of the
steepest slope and confne the water
TO a simple strip. The bed of each
strip is carefully graded to a uniform
slope, although the slope may change
TO conform to the contour of the
natural surface. The water to ir-
rigate each strip is taken from the
head ditch extending across the
upper edge Of the field, and is con-
trolled by an outlet box or border
gate, although the gates are some
times omitted to save in first cost Of
preparing for irrigation Check
gates. canvas dams or metal tappoons
are used to hold up the water in the
head ditch to cause it to flow into
the borders
This method is confined chiefly to
the irrigation of alfalfa and grain,
and in its various notifications is
used extensively in Arizona, Califor-
MIA and, to less extent, in Idaho,
Montana and other Rocky Mountain
states. 1t can be used best under
canals which deliver water to users
in large streams. since the smallest
head that can be applied successfully
is seldom less than or cubic feet
per second. but heads of to 10
cubic feet per second are the rule
1t is adapted especially to light, open
soils. into which water percolates
rapidly, as the use Of a large stream
confined between borders makes il
possible to force water over the sur.
face without great loss by per
collation.
on the university farm at Davis
Cal. the borders or lands average
about so feet wide by 900 feet long
Each levee has base feet wide ane
is ~ inches high, when newly made
bat settles to about 10 inches before
the first crop is harvested. The bee
OF each strip is leveled cross wise anC
slopes regularly from top to bottom
In preparing the surface of this
field the barley stubble was burned
then the soil was disked anf
roughly graded The location o
each border was marked out, eithe
by a drag Of by making a furrow
Sufficient earth to form the borde
was obtained by skimming the sur
face with scrapers. The scrape
teams began next to the head ditcl
and worked down. They crossed an,
re crossed the field at right angles
to the borders. and as a scrape
passed border marking it wa
dumped. Each scraper width of thu
borders was made up of two loads
but the last load over-lapped the frs
by half the width of the scraper
The surface of each border was thei
leveled to within OIL or O foot o
accuracy. The levees when frs
built We're rough, irregular and steep
They were cut down to a uniform
grade by homemade device calle'
planer.
in Imperial Valley Cal. a 40-acr
tract is divided into 2 lands, eacl
SO feet wide and a mile long Whei
the slope is too steep the lands rul
diagonally across the tract In orde
to lessen the FIRST cost for materia
for the borders, instead of bein