Practical Soil Moisture Interpretations for Various Soils Textures and Conditions to Determine Liquid Waste Volume Applications not to exceed AWC.
Table 27 should be used to determine the AWC at the time of application and the liquid volume in acre-inches that can be applied not to exceed the AWC. To determine the AWC in the upper eight inches, use a soil probe or similar device to evaluate the soil to a depth of eight inches.
| Table 27. Available Water Capacity. | ||||
| Available Moisture in the Soil | Sands and Loamy Sands | Sandy Loam and Fine Sandy Loam | Very Fine Sandy Loam, Loam, Silt Loam, Silty Clay Loam | Sandy Clay, Silty Clay, Clay, Fine and Very Fine Textured Soils |
|---|---|---|---|---|
| <25 % Soil Moisture | Dry, loose and single-grained; flows through fingers. | Dry and loose; flows through fingers. | Powdery dry; in some places slightly crusted but breaks down easily into powder. | Hard, baked and cracked; has loose crumbs on surface in some places. |
| Amount to Reach AWC | 20,000 gallons per acre | 20,000 gallons per acre | 40,000 gallons per acre | 27,000 gallons per acre |
| 25-50% Soil Moisture | Appears to be dry; does not form a ball under pressure. | Appears to be dry; does not form a ball under pressure. | Somewhat crumbly but holds together under pressure. | Somewhat pliable; balls under pressure. |
| Amount to Reach AWC | 15,000 gallons per acre | 20,000 gallons per acre | 30,000 gallons per acre | 20,000 gallons per acre |
| 50 to 75% Soil Moisture | Appears to be dry; does not form a ball under pressure. | Balls under pressure but seldom holds together. | Forms a ball under pressure; somewhat plastic; sticks slightly under pressure. | Forms a ball; ribbons out between thumb and forefinger. |
| Amount to Reach AWC | 10,000 gallons per acre | 13,000 gallons per acre | 20,000 gallons per acre | 13,000 gallons per acre |
| 75% to Field Capacity | Sticks together slightly; may form a weak ball under pressure. | Forms a weak ball that breaks easily, does not stick. | Forms ball; very pliable; sticks readily if relatively high in clay. | Ribbons out between fingers easily; has a slick feeling. |
| Amount to Reach AWC | 5,000 gallons per acre | 7,000 gallons per acre | 11,000 gallons per acre | 7,000 gallons per acre |
| 100% Field Capacity | On squeezing, no free water appears on soil, but wet outline of ball on hand. | On squeezing, no free water appears on soil, but wet outline of ball on hand. | On squeezing, no free water appears on soil, but wet outline of ball on hand. | On squeezing, no free water appears on soil, but wet outline of ball on hand. |
| Above Field Capacity | Free water appears when soil is bounced in hand. | Free water is released with kneading. | Free water can be squeezed out. | Puddles: free water forms on surface. |
| Source: USDA-Natural Resources Conservation Service (NRCS), Ohio Field Office Technical Guide. Used by permission. | ||||