Subsurface Drip vs. Overhead Irrigation
A Comparative Agronomic Analysis of Subsurface Drip
and Overhead Irrigation of Georgia Cotton
Watermark sensors were installed in two replicates of
each treatment. The sensors were placed between
the center two rows of the plot. One set was placed
in the row center at the depths of 6”, 24”, and 36”.
Another set was placed 4” away from the cotton at
depths of 8”, 16”, and 24”. Irrigation was triggered in
a treatment when any of the watermarks read above
40 cb. Adcon telemetry equipment was also installed
in one replicate of the four treatments to continously
monitor soil water status.
Monitoring Soil Water Status
Overhead irrigation systems are widely used in
irrigated cotton farmland. However, the
success of subsurface drip systems in other
crop systems has led researchers and
producers to consider it as an alternative to
overhead irrigation. However, the profitability
of subsurface drip compared to overhead
irrigation has not been widely assessed in the
Contact The University of Georgia
Drip irrigation can reduce water loss through soil evaporation, and
advantages of drip include more efficient water use, quicker
application to crops approaching water deficit, and the ability to farm
square fields efficiently without the loss of land at the corners. The
University of Georgia is comparing overhead irrigation and drip irrigation
for efficiency and cost.
Jared Whitaker, Craig W. Bednarz, Glen Ritchie, and Cory Mills
Irrigation of Treatments
Funding for this research was provided by Cotton Incorporated.
Data Analysis of cotton growth and yield among all
treatments was performed in SAS 8.0, using ANOVA at a
confidence level of 0.05 and Tukey’s pairwise test.
The cotton picked from the plots was ginned and weighed at the