Ag Alert May 21, 2025

Sensors Continued from Page 6 and tree nut grower who uses FloraPulse in his family’s orchards. Sohnrey has used the Pressure Bomb Express app for several years and said his father appreciates how easy it is to use and likes being able to check plant water status from his smartphone. “Several times I wouldn’t think I need- ed to irrigate yet, and it’s like, oh, wow, I definitely need to irrigate,” Sohnrey said. “Other times, it said we were actually re- ally wet, and you can watch it trend on the graph. It gives you more insight into the tree and what it’s doing at certain times.” FloraPulse this year introduced a 7-mil- limeter unit that is 50% smaller, more ac- curate, more reliable and better sealed to resist environmental factors, Santiago said. “The original one worked great for al- monds and prunes, but we found out in some crops like winegrapes and citrus, it was necessary to measure stem water po- tential in the outer xylem,” he said. In the past, FloraPulse recommended the unit for trunks or branches at least 2 inches in diameter. The smaller model can be used on trunks or branches of about a 0.75-inch diameter. The company has more than 150 units in almond and prune orchards statewide. Santiago said the company still doesn’t recommend the device for walnuts be- cause the tree produces fluid around the wound site, which hampers accurate read- ings. Shackel is conducting research to try to improve its use in walnuts. In pistachios, Santiago said FloraPulse has produced in- consistent results. The Phytech system, on the other hand, is based on dendrometers—precision sen- sors that attach to a tree trunk and mea- sure microscopic changes in diameter throughout the day, said Ziv Attia, Phytech global head of agronomy. Well-watered plants have a consistent pattern of trunks shrinking slightly throughout the day as water tension rises in the xylem. As they rehydrate, trunks expand overnight. If a tree is under stress, the maximum daily shrinkage becomes more pro- nounced, and overnight recovery is incom- plete. By measuring the daily shrinkage and growth values and using a crop-specif- ic algorithm, Attia said growers can easily identify which blocks are under stress days before visible symptoms appear. Phytech’s measurements, paired with irrigation duration and quantity, soil mois- ture readings, weather data and satellite imagery, give users real-time insight into plant health and water demand, he said. “Growers gain a holistic point of view of their water management practices— understanding not just how much water they’ve applied but how it moves through the soil profile,” Attia said. “Most impor- tantly, they see how the orchard is re- sponding on a daily basis.” Sensor placement is tailored to grow- ers’ specific goals, whether they want to monitor a representative area of a block or focus on a historically underperform- ing section. Satellite imagery, historical yield data and plant variety help guide

sensor placement. In a Nonpareil-Monterey almond or- chard, for example, placing one unit on each variety can help growers fine-tune ir- rigation across varietal differences, he said. The company serves more than 400,000 acres of cropland worldwide, with the bulk of the sensors being deployed on perma- nent crops. Vicky Boyd is a reporter in Modesto. She may be contacted at agalert@cfbf.com.

Some winegrape growers have tapped the Phytech technology to determine the start of veraison, or the ripening process, and when to begin regulated deficit irrigation to enhance fruit quality.

With chemistry that targets key fungal diseases, provides longer lasting residual control and adapts to stay ahead of disease resistance – Cevya ® fungicide delivers next-generation performance to protect your crop and your investment. Learn more at Cevya-Fungicide.com.

May 21, 2025 Ag Alert 7