CroPMan Programs Aid Growers
Computer models help growers irrigate crops efficiently
By Danielle Supercinski, May 2005
For more information regarding this subject, contact:
Tom Gerik
Crop simulation models have been developed and used by the research community to simulate the impact that cropping practices have on yield and natural resources—soil, water and air.
Many models are only designed to simulate the growth of specific crops, but the EPIC model is capable of simulating a wide variety of crops and cropping practices. In recent years, two Windows-based decision aids, CroPMan and WinEPIC, were developed by Drs. Tom Gerik, Wyatte Harman, Jimmy Williams and others at the Blackland Agricultural Research and Extension Center. They wanted to harness the capability of the EPIC model so Texas growers and Cooperative Extension could readily identify the most effective cropping practices that conserve water for irrigation and improve production and profitability.
“CroPMan and WinEPIC are being field tested with growers, Texas Cooperative Extension and Texas Agricultural Experiment Station researchers in South Texas to identify cropping practices and monitoring technologies that most effectively conserve water applied through irrigation with minimal adverse impact on crop yield and profitability,” said Tom Gerik, Experiment Station Researcher at Blackland Agricultural Research and Extension Center in Temple.
“The project entails monitoring and assessment of current cropping practices on grower’s fields in the Rio Grande Valley, Coastal Bend, Upper Gulf Coast and Texas Winter Garden (near Uvalde).”
CroPMan is used to assess “real-time” situations in the field—estimating crop and soil-water-fertility status, and to project implications of additional irrigation and fertilization (i.e., timing and amount) on crop productivity, Gerik said.
“CroPMan is designed to be used by Extension specialists and agricultural consultants,” he said. “Many of EPIC’s features are hard-wired and streamlined for Texas.”
CroPMan contains a feature known as “Projected Run,” which enables the user to assess the “real-time” status of a crop by stopping the model on any date of interest. The user can then update the soil or crop status, or alter subsequent management operations. They can estimate crop yield using 30 o 100 location specific weather scenarios through the end of the growing season. This feature assists growers with decisions on replanting, late planting, irrigation timing management and estimates of yield. CroPMan provides graphical outputs of numerous growth characteristics, crop stresses, economical variables and pesticide fate variables.
“WinEPIC was designed to provide researchers with all the features, power and flexibility as EPIC,” Gerik said.
WinEPIC is used to determine long-term implications of new irrigation practices, such as conversion of furrow irrigation to sub-surface drip and/or low energy spray application (LESA)/low energy precision application (LEPA) sprinklers, and comparisons of single cropping (monocrop) and double cropping systems.
“In WinEPIC the user can manipulate EPIC’s control files to simulate the full range of cropping scenarios,” he said. “The user can compare results of hundreds of scenarios (runs) through the batch mode.”
WinEPIC does not contain the ‘Projected Runs’ feature or graphical output of results found in CroPMan. However, all data are stored in Microsoft Access tables where the user can view and export the data for further manipulation, and both programs use the Microsoft Access structure to operate.
“The databases are constructed for the five distinct agricultural regions of Texas – West, South, Central, East and the Lower Rio Grande Valley,” Gerik said.
Each database contains tables with actual soil data, historical weather data, field operations, common crops and cropping systems, crop parameters, machinery/equipment, and numerous control type files. The field operation budgets include information on the type and timing of cultural practices such as tillage operations, irrigation, fertilization, planting date and harvest date.
“All operation budgets can be edited to produce the desired cropping practices of the user,” Gerik said. “Daily weather files and weather stations can be updated and created through a complementary software utility named the Crop Weather Analyzer.”
CroPMan, WinEPIC and the Crop Weather Analyzer are available on CD-ROM or can be downloaded from the CroPMan website or by contacting Tom Gerik.
