Maize Irrigation Study, 2002, Georgia Coastal Plain

Yield Comparisons:
Study:

Research Objective: Determine the effects of soil moisture pattern on corn yield and on stalk and root diseases.
Treatments:
 1.LEPA - apply 1" when sensor is less than 35cb
 2.LDN - apply 1" when sensor is less than 35cb
 3.No irrigation
 4.Same as treatment 2, delay 2 days
 5.No irrigation in June
 6.3 irrigations only - apply 1 inch the week before, 1 inch during, and 1 inch after tassel
 7.No irrigation after 1st tassels seen
 8.Same as treatment 2, plus 1" in 2 days
 9.Apply when 30" sensor is less than 35cb

Basic Crop Management: PLANTED - 20 Mar 2002; HARVEST - 05 Aug 2002 ; TILLAGE - Moldboard Plow (30 cm deep plus smoothing and bed shaping), wheel traffic controlled at 1.2 m centers; FERTILIZATION - Typical Extension Recommended Rate; WEED & PEST CONTROL: Typical Extension Recommendations.
Chronological Treatment and Observation Details
Cost Breakdown

Observations and data sets for individual treatments (crop years) follow:
Treatment 1:
LEPA - apply 1" when sensor is less than 35cb
  • Irrigation Dates and Amounts: Text Format;
  • Phenology: Emergence - 01 Apr 2002; Maturity (Black layer) - 19 Jun 2002
  • Stand Counts: Text Format;
  • Plant Heights: Text Format;
  • Ear Evaluations: Text Format;
  • Soil Water Pressure Observations: Watermarks
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 12.43; Individual plots - 12.67, 11.81, 12.17, 13.07 Text File
Treatment 2:
LDN - apply 1" when sensor is less than 35cb
  • Irrigation Dates and Amounts: Text Format;
  • Phenology: Emergence - 01 Apr 2002; Maturity (Black layer) - 19 Jun 2002
  • Stand Counts: Text Format;
  • Plant Heights: Text Format;
  • Ear Evaluations: Text Format;
  • Soil Water Pressure Observations: Watermarks
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 12.69; Individual plots - 11.85, 14.17, 13.20, 11.53 Text File
Treatment 3:
No irrigation
  • Phenology: Emergence - 01 Apr 2002; Maturity (Black layer) - 19 Jun 2002
  • Stand Counts: Text Format;
  • Plant Heights: Text Format;
  • Ear Evaluations: Text Format;
  • Soil Water Pressure Observations: Watermarks
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 0.92; Individual plots - 1.66, 1.15, 0.00, 0.87 Text File
Treatment 4:
Same as treatment 2, delay 2 days
  • Irrigation Dates and Amounts: Text Format;
  • Phenology: Emergence - 01 Apr 2002; Maturity (Black layer) - 19 Jun 2002
  • Stand Counts: Text Format;
  • Plant Heights: Text Format;
  • Ear Evaluations: Text Format;
  • Soil Water Pressure Observations: Watermarks
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 12.95; Individual plots - 13.06, 13.38, 13.54, 11.81 Text File
Treatment 5:
No irrigation in June
  • Irrigation Dates and Amounts: Text Format;
  • Phenology: Emergence - 01 Apr 2002; Maturity (Black layer) - 19 Jun 2002
  • Stand Counts: Text Format;
  • Plant Heights: Text Format;
  • Ear Evaluations: Text Format;
  • Soil Water Pressure Observations: Watermarks
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 6.04; Individual plots - 6.90, 8.06, 4.90, 4.32 Text File
Treatment 6:
3 irrigations only - apply 1 inch the week before, 1 inch during, and 1 inch after tassel
  • Irrigation Dates and Amounts: Text Format;
  • Phenology: Emergence - 01 Apr 2002; Maturity (Black layer) - 19 Jun 2002
  • Stand Counts: Text Format:
  • Plant Heights: Text Format;
  • Ear Evaluations: Text Format;
  • Soil Water Pressure Observations: Watermarks
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 5.59; Individual plots - 6.30, 5.52, 5.99, 4.53 Text File
Treatment 7:
No irrigation after 1st tassels seen
  • Irrigation Dates and Amounts: Text Format;
  • Phenology: Emergence - 01 Apr 2002; Maturity (Black layer) - 19 Jun 2002
  • Stand Counts: Text Format;
  • Plant Heights: Text Format;
  • Ear Evaluations: Text Format;
  • Soil Water Pressure Observations: Watermarks
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 3.08; Individual plots - 3.79, 1.24, 3.52, 3.76 Text File
Treatment 8:
Same as treatment 2, plus 1" in 2 days
  • Irrigation Dates and Amounts: Text Format;
  • Phenology: Emergence - 01 Apr 2002; Maturity (Black layer) - 19 Jun 2002
  • Stand Counts: Text Format;
  • Plant Heights: Text Format;
  • Ear Evaluations: Text Format;
  • Soil Water Pressure Observations: Watermarks
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 11.95; Individual plots - 13.58, 12.90, 10.26, 11.06 Text File
Treatment 9:
Apply when 30" sensor is less than 35cb
  • Irrigation Dates and Amounts: Text Format;
  • Phenology: Emergence - 01 Apr 2002; Maturity (Black layer) - 19 Jun 2002
  • Stand Counts: Text Format;
  • Plant Heights: Text Format;
  • Ear Evaluations: Text Format;
  • Soil Water Pressure Observations: Watermarks
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 10.51; Individual plots - 11.97, 10.97, 8.64, 10.45 Text File
For more information on the study and its interpretation contact:
Dr. Jim Hook Professor, Soil and Water Management
Crop and Soil Sciences Department and NESPAL
The University of Georgia, College of Agricultural and Environmental Sciences
P.O. Box 748, Tifton, GA 31793-0748
e-mail: jimhook@tifton.cpes.peachnet.edu

Page developed by James E. Hook, Amanda Richards, and Linsey Forlow.
Last Modified on 18 March 2003.