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Guideline for Estimating Soil Moisture

Available Water Holding Capacity of Various Textured Soils:

Available Water Capacity, AWC (Inches/Foot)
AWC
Coarse Texture
Fine Sand and Loamy Fine Sand
Moderately Coarse Texture - Sandy Loam and Fine Sandy Loam
Medium Texture - Sandy Clay Loam, Loam, and Silt Loam
Fine Texture-Clay, Clay Loam, or Silty Clay Loam
Range
0.6 - 1.2
1.3 - 1.7
1.5 - 2.1
1.6 - 2.4

Soil Moisture Deficits (SMD) in inches/foot based on described soil appearance:

Soil Moisture Deficits
Available Soil Moisture Percent
Coarse Texture
Fine Sand and Loamy Fine Sand
Moderately Coarse Texture- Sandy Loam and Fine Sandy Loam
Medium Texture - Sandy Clay Loam, Loam, and Silt Loam
Fine Texture-Clay, Clay Loam, or Silty Clay Loam
0 - 25
Dry,loose, will hold together if not disturbed, loose sand grains on fingerswith applied pressure.
SMD 1.2-0.5 
Dry, forms a very weak ball, aggregated soil grains break away easily from ball.
SMD 1.7 -1.0
Dry. Soil aggregations break away easily. no moisture staining on fingers, clods crumble with applied pressure.
SMD 2.1-1.1 
Dry, soil aggregations easily separate, clods are hard to crumble with applied pressure
SMD 2.4-1.2
25 - 50
Slightly moist, forms a very weak ball with well-defined finger marks, light coating of loose and aggregated sand grains remain on fingers.
SMD O.9-0.3
Slightly moist, forms a weak ball with defined finger marks, darkened color, no water staining on fingers, grains break away.
SMD 1.3-0.7
Slightly moist, forms a weak ball with rough surfaces, no water staining on fingers, few aggregated soil grains break away.
SMD1.6-0.8
Slightly moist, forms a weak ball, very few soil aggregations break away, no water stains, clods flatten with applied pressure
SMD 1.8-0.8
50 - 75
Moist, forms a weak ball with loose and aggregated sand grains on fingers, darkened color, moderate water staining on fingers, will not ribbon.
SMD O.6-0.2
Moist, forms a ball with defined finger marks. very light soil/water staining on fingers. darkened color, will not slick.
SMD O.9-0.3
Moist, forms a ball, very light water staining on fingers, darkened color, pliable, forms a weak ribbon between thumb and forefinger.
SMD 1.1- 0.4
Moist. forms a smooth ball with defined finger marks, light soil/water staining on fingers, ribbons between thumb and forefinger.
SMD l.2-0.4
75 - 100
Wet, forms a weak ball, loose and aggregated sand grains remain on fingers, darkened color, heavy water staining on fingers, will not ribbon.
SMD O.3-0.0
Wet, forms a ball with wet outline left on hand, light to medium water staining on fingers, makes a weak ribbon between thumb and forefinger.
SMD O.4-0.0
Wet, forms a ball with well defined finger marks, light to heavy soil/water coating on fingers, ribbons between , thumb and forefinger.
SMD O.5 -0.0
Wet, forms a ball, uneven medium to heavy soil/water coating on fingers, ribbons easily between thumb and forefinger.
SMD O.6-0.0
Field Capacity (100%)
Wet, forms a weak ball, moderate to heavy soil/water coating on fingers, wet outline of soft ball remains on hand.
SMD 0.0
Wet, forms a soft ball, free water appears briefly on soil surface after squeezing or shaking,medium to heavy soil/water coating on fingers.
SMD 0.0
Wet, forms a soft ball, free water appears briefly on soil surface after squeezing or shaking, medium to heavy soil/water coating on fingers.
SMD 0.0
Wet, forms a soft ball, free water appears on soil surface after squeezing or shaking, thick soil/water coating on fingers, slick and sticky.
SMD 0.0