We live on a planet where our most precious resource literally falls from the sky. But rain rarely occurs when you need it, as many cotton producers found during the 2010 growing season.

Fortunately, supplemental irrigation water can mitigate the unpredictable nature of weather, if it’s timed correctly and measured out in appropriate amounts with as efficient a distribution system as possible.

Cotton producers can pick up the latest on irrigation scheduling, research and methodology at the Irrigation Workshop, Wednesday, Jan 5 at the Beltwide Cotton Conferences. The workshop will be held in International 1-3, in the Atlanta Marriott Marquis, from 1:30 p.m. to 3:30 p.m.

The workshop will feature oral presentations as well as live demonstrations of several irrigation scheduling programs, according to Bill Robertson, the National Cotton Council’s Beltwide Conference coordinator and former Extension cotton specialist.

The two hour session, organized by Russell Nuti, research agronomist with USDA’s agricultural Research Service, and Ron Sorenson, USDA-ARS, will begin with three 20 minute talks on irrigation issues.

At 1:30 p.m., Glen Ritchie, University of Georgia, Soil and Crop Science Department, Tifton, Ga., will kick off the discussion by taking the cotton plant’s point of view. “I’m going to talk about water dynamics in the plant, from the roots to the stomata, and how various irrigation regimes affect those dynamics.”

Ritchie will support his observations with aerial imagery of cotton fields under various irrigation regimes. “What producers will learn is that there are times during the season when they can put on quite a bit less water. They’ll also find that if they focus on irrigation between first flower and six weeks after first flower, they can maximize their yield compared to irrigation at any other point during the season.”

At 1:50 p.m., Louis Baumhardt, USDA-ARS, Bushland, Texas, will discuss how practices such as no-till can reduce the amount of water that evaporates from the soil, thereby increasing the efficiency of irrigation. “We can yield about two bales with our low-irrigation rate compared to 650 pounds under tillage.”

Baumhardt will also present data which indicates that deficit irrigation producers may be better off by focusing water resources on fewer acres, rather than spreading water resources too thin.

Baumhardt has also found that center pivots using drop nozzles can produce yields comparable to a subsurface drip irrigation system.

At 2:10 p.m., Ronald Sorensen, USDA-ARS, of the National Peanut Research Laboratory in Dawson, Ga., will examine shallow subsurface drip irrigation for row crops in the Southeast. He is studying a drip irrigation system buried 2 inches under the surface in every other middle. Costs of installation is about two-thirds the cost of a deep, subsurface drip system.

“The system would allow a producer to go into a small irregular shaped field and put in this shallow, sub-surface drip system, economically and leave it there for three to five years,” Sorensen said.

Following the three talks, the speakers will participate in a panel discussion “for one-on-one time with growers and consultants,” said Nuti.

In an adjoining room, there will be a number of irrigation scheduling posters and demonstrations, with experts to answer questions.

Extension cotton specialist Randy Norton from Arizona will be doing a demonstration and a poster on water and irrigation management for Arizona cotton production systems.

There will also be a presentation on variable-rate irrigation, by Ken Stone, USDA-ARS, in South Carolina, using Irrigator Pro, irrigation scheduling software developed in Georgia.

Gretchen Sassenrath, USDA-ARS, Stoneville, Miss., and Amy Schmidt, Extension professor, Mississippi State University, will be on hand to demonstrate irrigation scheduling software.



More on the speakers:

Glen Ritchie

Glen L. Ritchie is an assistant professor at the University of Georgia, College of Agricultural and Environmental Sciences. His current work focuses on cotton growth and development, particularly due to water stress. He also conducts low-level remote sensing and GIS research, and teaches an introductory GIS course.


Ronald Sorensen

Ronald Sorensen is a research agronomist at the National Peanut Lab in Dawson, Ga. His research includes the development of more efficient management practices for conventional tillage systems with respect to agricultural water use for cotton, corn and peanuts.


Louis Baumhardt

Louis Baumhardt is a soil scientist with the Conservation and Production Research Laboratory in Bushland, Texas. His research focuses on efficient use of water in dryland agriculture, residue management for soil and water conservation, dryland crop rotations and sequences, integrated livestock and row crop production systems, computer crop growth modeling and rain infiltration and field hydrology.