Maize Irrigation Study, 1987, Georgia Coastal Plain

Yield Comparisons:
Study:

Research Objectives:

    1. Compare irrigation scheduling techniques for their ability to meet corn water needs - yield effects and water use efficiency
    2. Compare model predictions of soil water with measured soil water.
    3. Measure changes in water content by depth following infiltration of irrigated water. To determine "recoverable" water.
    4. Measure in-situ hydraulic conductivity with the Guelph permeameter, and ponded infiltration with the saturated and unsaturated infiltrometer.
Treatments:
 1.Ceres model - 50% trigger, 100% refill
 2.Fixed schedule
 3.CBWB model - 50% trigger, 100% refill
 4.Control - Tensiometer - vary - full season
 5.Irrigate twice weekly with 80% evaporation pan
 6.No irrigation

Basic Crop Management: PLANTED - 01 Apr 1987 (rows 0.9m apart, placed 2.5-3 cm deep); HARVEST - 10 Aug 1987 (2-row grain combine); 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

Observations and data sets for individual treatments (crop years) follow:
Treatment 1:
 Ceres model - 50% trigger, 100% refill
  • Irrigation Dates and Amounts: Text Format;
  • Phenology: Emergence - 13 Apr 1987; Pollination (R2) - ; Maturity (Black layer) - 20 Jul 1987
  • Stand Count:
  • Soil Water Pressure Observations: Tensiometer & Gypsum Block
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 8.89; Individual plots - 8.18, 9.94, 8.41, 9.02 Text File
Treatment 2:
 Fixed schedule
  • Irrigation Dates and Amounts: Text Format;
  • Phenology: Emergence - 13 Apr 1987; Pollination (R2) - ; Maturity (Black layer) - 20 Jul 1987
  • Stand Count:
  • Soil Water Pressure Observations: Tensiometer & Gypsum Block
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 9.47; Individual plots - 10.47, 8.16, 10.44, 8.79 Text File
Treatment 3:
 CBWB model - 50% trigger, 100% refill
  • Irrigation Dates and Amounts: Text Format;
  • Phenology: Emergence - 13 Apr 1987; Pollination (R2) - ; Maturity (Black layer) - 20 Jul 1987
  • Stand Count:
  • Soil Water Pressure Observations: Tensiometer & Gypsum Block
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 9.26; Individual plots - 9.79, 6.46, 10.19, 10.61 Text File
Treatment 4:
 Control - Tensiometer - vary - full season
  • Irrigation Dates and Amounts: Text Format;
  • Phenology: Emergence - 13 Apr 1987; Pollination (R2) - ; Maturity (Black layer) - 20 Jul 1987
  • Stand Count:
  • Soil Water Pressure Observations: Tensiometer & Gypsum Block
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 10.50; Individual plots - 9.92, 10.67, 11.72, 9.69 Text File
Treatment 5:
 Irrigate twice weekly with 80% evaporation pan
  • Irrigation Dates and Amounts: Text Format;
  • Phenology: Emergence - 13 Apr 1987; Pollination (R2) - ; Maturity (Black layer) - 20 Jul 1987
  • Stand Count:
  • Soil Water Pressure Observations: Tensiometer & Gypsum Block
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 10.70; Individual plots - 10.59, 11.42, 10.48, 10.30 Text File
Treatment 6:
 No irrigation
  • Irrigation Dates and Amounts: Text Format;
  • Phenology: Emergence - 13 Apr 1987; Pollination (R2) - ; Maturity (Black layer) - 20 Jul 1987
  • Stand Count:
  • Soil Water Pressure Observations: Tensiometer & Gypsum Block
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 5.58; Individual plots - 4.89, 6.32, 6.20, 4.89 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 29 June 2000.