The mirror. (Stillwater, Minn.) 1894-1925, 1916-05-11

Where the water is under little or no
pressure, either vitrihed clay o. cement
pipes are sometime used, particularly in
southern Californa. The distributing of
water by means of underground pipes and
hose>ls, however, to expensive for irrigation
on large scale. The open ditch, which
takes the water out of the larger canal OF
reservoir to the land to be irrigated is made
to follow the contour of the land so that the
flow is moderate and uniform and the water
can be readily distributed to lateral bitches,
or fumes. at any desired point. The
simplest manner of turning water from a
ditch is to cut hole in the side and to use
earth to make a dam in the ditch; an i'm
provement on this method is the use of
portable cloth, wood, or metal dams. The
water is spread over the land by variety
OF methods which belong, as a rule, in
three main classes mainly.
l. Flooding
2. Furrow Irrigation
y.
In the first class, that OF flooding, the
bitches or laterals are carried along the
higher parts of the field and the water is
released by spade cuts at intervals in the
banks; or, it is made to overflow the banks
by means of dams. This is the oldest and
simplest method of irrigation 1t is best
suited to small grains and forage plants
which are sown broadcast, and is most eff
fective with nearly level bitches and on land
of uniform grade.
The second class, Furrow-irrigation, or
running water in burrows between the rows
of crops, is again the simplest and cheapest
and most widely used method of irrigation
of crops, which can be grown to advantage
in rows and is adapted to a wide range of
slope and soil conditions. If the slope is
not too great to carry a small stream with
out excessive washing the rows are run
straight down the grade from the supply
ditch or fume which occupies the crest of
the highest ground: otherwise, the rows are
run at an angle giving the proper grade.
The length of burrows that can be used de-
ponds upon the character of the soil and
the head of the water. The more porous
the soil, the larger should be the stream or
the shorter the furrow. For most field
and garden crops a larger stream and a
shorter run are used than for fruit trees |
Lateral or supply bitches are usually taken
across the slope of the land at intervals of
about forty rods. The laterals should be
as nearly level as possible so that they may
be kept full and will discharge a uniform
amount of water through the openings into
he burrows.
The third class, that of Sub irrigation,
'r the distributing by means of underground |
pipes with suitable outlets or from tile |
Trains or blind bitches, from which the |
water can rise the roots of the plants by
This method is expensive and |
If doubtful practicability, except on a
United scale in greenhouses and other |
horticultural work. A similar method, |
Known as underhow-irrigation'' consists |
n opening burrows at considerable distances |
part and keeping them filled with water
Until the ground water rises, SO that it can
each the roots of plants by capilarity. |
This method is little used.
| believe any method to be of value must
ecure the following results:
L. The distributing of the moisture
venly throughout the soil-mass to as great
depth as possible, providing it does not
ink beyond the reach of the plant by root
extension, nor beyond recovery by capil-
airy use.
?. Economy of labor, both in aggregate
ime and in the feasibility of operating
without employment of extra hands,
3. Economy of water in the prevention
# waste by overflow or evaporation, or by
apid percolation, and in placing the water
where it will do the most good.
4. Leaving the land in the best condition
L
18th which coqserves moisture and at the
anne time favors thrift in the plant.
Crops sown broadcast can be irrigated
My by flooding or sprinkling. Flooding
5 also adapted to very loose soils. The
ontour, check and furrow method is best
uited to cultivation by horse power, which
a matter of great importance, since thoro
to overcome the compacting
-rigation and to secure soil mulch should,
d all cases, follow as soon after irrigation
S the condition of the soil will permit.
Deep and thoro preparation of the soil
Increases its storage capacity for water and
-equent cultivation of the surface reduces |
oss from evaporation, thus reducing ma
erially the amount of irrigation required
nd enabling the soil to utilize to the best
dvantage whatever rain fall may occur.
The DEVELOPMENT of IRRIGATION in the