George Goshgarian’s Watermark sensor system measures soil moisture throughout the soil profile and integrates data into a web-based portal where he can retrieve it in real-time or compare it to historical information.
Third-generation Fresno County almond grower George Goshgarian Jr. is investing time and technology to better understand the irrigation needs of his almond orchard and to time irrigation sets and rates using data from real-time monitoring of soil, climate conditions and tree use.
Goshgarian, who farms 400 acres
of permanent crops with his father, George Sr., this year installed a system that combines Watermark soil moisture sensors, on-site weather stations and sap flow sensors to base his irrigation decisions on tree need and use.
“With this technology I think we can really hone in on what the trees need rather than rely on theoreticals,” Goshgarian said.
Goshgarian’s transformation on his 400 acres of almonds and other trees and vines illustrates how almond growers can move up the Almond Irrigation Improvement Continuum. The continuum is part of the Accelerated Innovation Management Program (AIM), a strategic effort by the Almond Board of California (ABC) to make growers more efficient and sustainable as they address the challenges of the next century.
Guidance on how almond growers can incorporate new technologies and strategies to move up the Irrigation Continuum has been aggregated at the Almond Board’s website under the Irrigation Continuum tab.
ABC’s Gabriele Ludwig said at the continuum’s Irrigation 1.0 level all growers should be incorporating practices in each of five key areas:
- Evaluating soil moisture
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Evaluating plant water status
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Determining applied water
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Estimating orchard water requirements based on evapotranspiration rates
- Assessing irrigation system performance and efficiency
While Goshgarian for several
years has relied on CIMIS ET data, tensiometers and visual assessment to generally understand irrigation needs in his orchard, a more refined system that provides regular, real-time data to fine-tune adjustments in his irrigation scheduling moves him into a higher level along the continuum, Ludwig said.
Gypsum Blocks
The gypsum block system measures soil moisture in one-foot increments throughout the soil profile. Weather stations are located within each 40-acre block to provide site-specific climate information. Data is collected and generated in real time so that Goshgarian will be able to pull up current information on his computer to understand what is happening in the orchard at any given time.
“I monitor the soil moisture
in order to stay ahead of my irrigation curves. When trees start waking up you can see it drying out because roots are pulling water out of the first couple feet of the profile,” Goshgarian Jr. said.
He is working to develop a system that integrates that information with data about temperature, wind speed and solar radiation to get a full picture of water needs in the orchard. While sap flow sensors are not refined for almonds as is the measurement of stem water potential with pressure chambers, he hopes the sensors will be an indication of tree water status and will help confirm what suggestive data in the orchard is telling him.
Goshgarian is experimenting with sap flow sensors to see if measurements of tree water use confirm he is using data to schedule irrigations for maximum benefit to the tree.
Sap Flow System
“We are switching slowly over to the sap flow system and some of the information we are generating is becoming very interesting in terms of tying the soil moisture data in with solar radiation and other weather station data.”
Site-specific data also helps account for extreme variations of soil type or variations in microclimate within the orchard that might impact water use differently.
“The data set is a combination
of real-time information from
the weather stations, soil profile monitoring and sap flow, that hopefully will paint a pretty accurate picture so that by the end of this year we will have a nice big data set that will tell us how best to apply all the technology to hone in on what the tree needs instead of theoreticals,” he said. “We are trying to take all the guessing out of it.”
