Automation Can Save Irrigation Water and Keep Groundwater CleanBy Don Comis
January 23, 1998
For the past four summers, cotton plants on a test site in Lubbock, Tex.,
have had all their water needs met by computer, with no waste of water or
fertilizers and other dissolved chemicals.
The computer decides whether to turn on irrigation pumps based on readings
from soil probes, combined with weather updates every half hour plus information
from a computer model on crop water use. The prototype, still in the research
stage, is believed to be the only such totally automated irrigation management
system in the country.
Steven R. Evett, a soil physicist with the
Agricultural Research Service in
Bushland, Tex., designed a key component of the system: the electronic probes
that give the computer soil moisture readings on the half hour. He also wrote
the computer program that drives the soil moisture readings.
A Texas A&M University team in Lubbock, led by soil physicist Robert J.
Lascano, wrote programs that combine water content and weather data and
automatically make irrigation decisions.
Dynamax, Inc., a Houston firm that sells and manufactures scientific
instruments, sells the probes. Working with the company and Evett, Lascano has
demonstrated the workability of joining the probes with a field weather station
and the computer model of crop water use he designed. Evett adapted the model
for personal computers and continues to update it. The model can be downloaded
from the World Wide Web at:
An article on the system appears in the January issue of ARS' Agricultural
Research magazine. The article also is on the World Wide Web at:
Scientific contact: Steven R. Evett, USDA-ARS
Conservation and Production Research
Laboratory, P.O. Drawer 10, Bushland, Texas, phone (806) 356-5775, fax