Feel test tells when to irrigate

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The "Feel" Test
Tells When to Irrigate
Guide 400 A-111
Although many devices have been used to determine when to irrigate, none of them are well suited
to New Mexico field conditions. These methods are
either too expensive or too complex to be practical.
One method that gives good results is the "feel" test.
By feeling the soil and observing its different signals
at different levels of moisture content, you can tell
when to irrigate. No equipment other than a "sharpshooter" spade or a soils auger is needed. If we roughly
divide all soils into four types, each type will have certain "tell tale" signs which can be seen or felt at a
particular moisture content.
Using these symptoms or characteristics as a guide,
you can test the total root zone of your crop (one test
every six inches) and average the percentages obtained
to get a good idea of moisture remaining in the soil.
Soil can store only a certain amount of water per
foot of depth:
Sandy  (coarse)
Silts and clay loams
Clays  (heavy)
SOIL MOISTURE INDICATORS — THE FEEL TEST
Degree of
Percent Useful
Soil    Moisture
Soil  Type
Dry, loose, single-
through fingers.
light
Dry,  loose, flows
through fingers.
Medium
Powdery,  dry,  sometimes
slightly crusted  but
easily breaks down into
powdery conditions.
Heavy to Very Heavy
Dry
0
Hard,  baked, cracked;
sometimes has loose
crumbs on surface.
u.
50 or less
Still appears to
be dry; will not
form a ball with
pressure.
Still appears to
be dry; will not
form a ball.
Somewhat crumbly, but
will  hold together
from pressure.
Somewhat pliable;
will ball under
Fair
50 to 75
texture under 50
Tends to ball
under pressure
but seldom will
hold together.
Forms a ball and is
very pliable,   slicks
Easily ribbons
out between fingers,
has a slick feeling.
Excellent
75 to field
Tends to stick together slightly;
very weak ball
Forms weak ball,
will  not slick.
Forms a ball and is
very  pliable;   slicks
high in clay.
Easily ribbons out
between fingers,
has a slick feeling.
Ideal
At field
capacity
Upon squeezing, no
soil but wet outline
of ball is left on
Same as coarse.
Same as coarse.
Too wet
Above field
when soil is bounced
Free water will
be released  with
kneading.
Can squeeze out free
Puddles and free
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