|Soil Moisture in Georgia|
|ÿ||August 6, 1999||August 7, 1998||5-Year Avg.|
Source: Georgia Agricultural Statistics Service
ATHENS, Ga. - After a month of little rain and intense heat, severe drought conditions have returned to parts of north and middle Georgia. Lack of topsoil moisture is a major concern across the state.
The Georgia Agricultural Statistical Service reports that moisture is short to very short in 80 percent of the state's soils. Last year at this time, in a dry summer, soil moisture was rated as short to very short in 60 percent of the soils. The average over the past five years is 32 percent.
Soil Moisture Low
Soils are very dry in southwest Georgia, with potential crop yields being severely cut because of dryness, according to the August 7 Crop Moisture Index. Soils in northeast, west central and central Georgia are excessively dry, with yield prospects reduced.
The CMI rates soils in north central, east central, south central and southeast Georgia as abnormally dry, with yield prospects deteriorating. The soil moisture in northeast Georgia is rated as short.
Many places in north and middle Georgia received less than a third of their normal rainfall during the past four weeks (July 14 through Aug. 10). Some had less than a fourth of normal rainfall, including Athens (0.80 inches) and Blairsville (0.98).
Augusta (0.08 inches), Columbus (0.31), Macon (0.58) and Rome (0.41) each had less than a fifth of normal rainfall.
Palmer Drought Severity Index
The Palmer Drought Severity Index is the most commonly used drought index in the United States. The PDSI classifies long-term drought conditions, primarily to assess hydrological conditions. It is not a good index for most agricultural purposes.
As of Aug. 7, the PDSI classifies all of Georgia except the northwest corner in moderate to severe drought. The northwest corner is in mild drought.
Soil moisture loss from evapotranspiration ranged from 1.25 to 1.5 inches across the state last week. With the current evapotranspiration rates, the state will continue to lose soil moisture even with normal rainfall.
Above-normal rainfall will be needed to end drought conditions. According to the PDSI calculations, the northeast, west central, central, southwest and south central Georgia need more than six inches of rain to end the drought.
(David Emory Stooksbury is associate professor of Biological and Agricultural Engineering at University of Georgia's College of Agricultural and Environmental Sciences.)