By DAVID F. ZOLDOSKE
Center for Irrigation Technology,
California State University, Fresno

Now that many of us have access to a personal computer at home or in the workplace, the opportunity to develop an irrigation schedule guide for agricultural crops now exists through the World Wide Web.

The scheduling can be done through the use of a new program called Wateright, which is located at www. wateright.org .

The program was developed by the Center for Irrigation Technology with significant support from the U.S. Bureau of Reclamation.

Wateright is linked to the California Irrigation Management Information System (CIMIS). There are 94 weather stations linked to CIMIS, which provides evapo-transpiration data for specific sites throughout California. The program references the CIMIS weather stations to develop site-specific irrigation scheduling guidelines in California. Future plans call for expanding Wateright to other states which provide weather station networks or individuals that have weather stations on-site.

PROGRAM'S PURPOSES

Wateright is designed to be both an educational tutorial about weather-based irrigation scheduling and to provide irrigation schedule guidelines for local sites.

The tutorial utilizes animation and text examples to educate the user on weather-based irrigation scheduling principles and practices. The program will serve homeowners and those in turf, landscaping and agriculture.

A grower can develop an irrigation-scheduling guide by answering a few field specific questions. The first step is to print out a questionnaire from Wateright. The questions include specifics on your irrigation system and equipment, soil type, crop selection and planting date (for annuals). This needs to be filled out in advance of actually creating the scheduling guide. You do not want to get halfway through the set up and find you don't have the required information.

Wateright does provide some default values for management allowed deficiency (MAD) and distribution uniformity (DU) as a starting point in developing irrigation scheduling guidelines.

The next step is to select a nearby CIMIS station, which will be used as the reference for establishing the irrigation schedule guide. This is done by selecting the appropriate county and within that county choosing the nearest or most representative CIMIS station.

Since weather conditions are what create plant water demand, it is important to select a reference which similar to your site.

An irrigation guide is developed using five-year historical data. Wateright compares the historically based irrigation guideline with current weather data and flags any run times that are significantly different than current weather conditions might predict.

The scheduling guide can be used to compare to current practices and provide impetus to further explore major differences between the two.

Wateright walks you through step-by-step to obtain the needed information. Wateright was designed so anyone, even with little or no irrigation experience, will be able to learn about weather-based irrigation scheduling and develop an irrigation-scheduling guide on his or her first visit to Wateright. As with all weather-based irrigation-scheduling guides, actual irrigation requirements need to be verified by observing the plant material and/or verifying soil moisture levels.

Wateright provides for a site-specific adjustment of the initial run time estimates for each field entered. The original estimates are set at 100%. Customizing of each field between 50% and 150% is achieved by utilizing a drop down box. This adjustment is applied each time the guidelines are generated to more accurately reflect your crops water requirements.

NOW AND INTO THE FUTURE

This program is just being released and surely will require fine-tuning and adjustments. There is a comment section available where we hope to hear from growers on what works well and where we can make improvements.

We see the development of this program as a long-term project, which will include enhancing current features and adding new ones.

We ultimately want to customize Wateright to fit the needs of irrigated agriculture. We can only meet this goal by having growers experience Wateright and giving us your thoughts.

Together we can make this a successful tool toward better water management.