Maize Irrigation Study, 1980, Georgia Coastal Plain

Yield Comparisons:
Study:

Research Objectives:

    1. Determine the number of stress days added by delaying irrigation for 1, 2, and 3 days.
    2. Observe soil moisture profiles resulting from delayed irrigation.
    3. Compare relative yield reductions caused by irrigation delay.
    4. Estimate the probabilities of accumulating rainfall during each delay period.
Treatments:
 1.Control - Tensiometer triggered - 15-60 cm at 30cb, on time
 2.Tensiometer triggered - 15-60 cm at 30cb, one day delay
 3.Tensiometer triggered - 15-60 cm at 30cb, two day delay
 4.Tensiometer triggered - 15-60 cm at 30cb, three day delay

Basic Crop Management: PLANTED - 28 Feb 1980 (rows 0.9m apart); HARVEST - 16 Jul 1980 (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:
 Control - Tensiometer triggered - 15-60 cm at 30cb, on time
  • Irrigation Dates and Amounts: Text Format;
  • Phenology: Emergence - 13 Mar 1980; Pollination (R2) - 02 Jun 1980; Maturity (Black layer) - 11 Jul 1980
  • Stand Count:
  • Soil Water Pressure Observations: Tensiometer & Gypsum Block
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 10.52; Individual plots - 12.33, 10.46, 8.59, 11.64, 11.66, 8.43 Text File
Treatment 2:
 Tensiometer triggered - 15-60 cm at 30cb, one day delay
  • Irrigation Dates and Amounts: Text Format;
  • Phenology: Emergence - 13 Mar 1980; Pollination (R2) - 02 Jun 1980; Maturity (Black layer) - 11 Jul 1980
  • Stand Count:
  • Soil Water Pressure Observations: Tensiometer & Gypsum Block
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 10.24; Individual plots - 12.28, 10.53, 11.29, 8.51, 10.13, 8.69 Text File
Treatment 3:
 Tensiometer triggered - 15-60 cm at 30cb, two day delay
  • Irrigation Dates and Amounts: Text Format;
  • Phenology: Emergence - 13 Mar 1980; Pollination (R2) - 02 Jun 1980; Maturity (Black layer) - 11 Jul 1980
  • Stand Count:
  • Soil Water Pressure Observations: Tensiometer & Gypsum Block
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 5.81; Individual plots - 6.83, 3.13, 7.21, 3.86, 6.65, 7.15 Text File
Treatment 4:
 Tensiometer triggered - 15-60 cm at 30cb, three day delay
  • Irrigation Dates and Amounts: Text Format;
  • Phenology: Emergence - 13 Mar 1980; Pollination (R2) - 02 Jun 1980; Maturity (Black layer) - 11 Jul 1980
  • Stand Count:
  • Soil Water Pressure Observations: Tensiometer & Gypsum Block
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 7.95; Individual plots - 11.33, 8.76, 5.81, 5.58, 9.67, 6.56 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.