Unleashing the Potential of Your Orchards with Tule Sensors
As a Tule customer, I’m delighted to contribute a guest blog post on the Tule website. I would like to share with you my journey and insights on harnessing the power of Tule sensors to optimize irrigation practices on our family farm. In this blog post, I will highlight our short-term and long-term wins with Tule, discuss my approach to utilizing the Tule data, and include a few cases where Tule data helped us identify and address issues in the orchards.
The Short Term and Long Term Benefits of Using Tule Sensors
At Nichols Farms, Tule sensors helped us with some small wins in the first year of use, but they’ve also achieved greater results over time.
During our first year using Tule sensors, they took the guesswork out of when and how much to irrigate so we had more time to spend in the field on other tasks. We could focus on “problem fields” that didn’t respond to water applications as we’d expected and scout them more. We were able to strategically irrigate to advance our harvest dates, reducing our pistachios’ vulnerability to navel orangeworm pressure. Our quality improved the first year as we irrigated to our trees’ water needs.
Over a few years, we were able to really dial in our efforts to irrigate to Actual Evapotranspiration (ETa). We’ve found that this practice has improved the overall plant health of our orchards. We’ve noticed better nutrient uptake by the root system, lower risk and outbreak of certain pests & diseases, and overall better quality and yields. Precision irrigation has also lead to improved predictability. With multiple years of ETa data, water budgeting becomes based on data versus guesswork. As SGMA regulations ensue, becoming more finite with irrigation management is necessary.
The Significance of Actual ET for Effective Water Management
The Actual Evapotranspiration value from the Tule sensor is the most important piece of information for our irrigation management. Through years of experience, I have noticed a consistent pattern: orchards with higher ETa values tend to be the most productive. A higher ETa value indicates that our orchards effectively utilize applied water, leading to increased nutrient uptake and increased photosynthesis. Consequently, we witness enhanced growth and higher yields.
Reference ET (i.e., CIMIS) and Crop Coefficients are not enough. You need Actual ET data. Irrigating an orchard with a disease based on University of California Crop Coefficient (Kc) values may exacerbate the problem. From my experience, the orchard with the highest ETa is not necessarily the orchard that received the most applied water. In one of our Tulare blocks, we irrigated using the published Kc values and struggled with Alternaria for many years. We installed a Tule sensor in 2020, which helped inform our decision to reduce irrigation going into August. We saw a beneficial response in disease mitigation.
Weekly Insights on the Tule Dashboard
On the Tule dashboard, I look at the inches applied relative to how much water the trees used (i.e., the ETa). In addition, I look at the FieldStat value, which is an evapotranspiration-based way to show the water stress of the trees. FieldStat tells me if the trees are using all the water they could use (i.e., FieldStat is 100%), or if the trees are thirsty and regulating their water use (i.e., FieldStat is less than 100%).
In the example above, all three pistachio blocks were recently harvested. Before harvest, we dried out the blocks with deficit irrigation and the FieldStat values were in the 60% range (i.e., more water stress than the current level). After harvest, we have applied more water and FieldStat has bounced back to 75-90%. Note that the trees are using less water than what we’ve applied. The trees are still recovering from the water deficits before harvest and we are intentionally adding moisture back to the soil.
Examples of Irrigation Decisions Based on Actual ET and FieldStat
Let’s dig deeper into one of the blocks, AKE C3,C4, which was one of our better-yielding blocks this year. We were aiming to delay hill split as long as we could to minimize splits from navel orangeworm. Around the week of July 11, we intentionally stressed the trees to induce hull split and limit hull rot. After the non-pareil harvest, the low FieldStat values told us that the trees could use more water than they currently were using. We irrigated more than the Actual ET to improve the plant water status and bring up soil moisture. The trees responded well to those applications and the FieldStat and ETa values jumped back up.
At a different ranch, we struggle with water infiltration, so trying to “catch up” is not an option for us. That is, once the trees become water stressed and the soil dries down, we cannot get water back into the soil quickly enough for the trees to recover. Because we can’t catch up from water deficits, we make sure to replace the Actual ET (i.e., the tree water use) with applied irrigation each week. In the month prior to harvest, you can see in the FieldStat data above that we successfully staved off water stress. In the FieldStat data, you can also see that we don’t get much of a response to applied water due to the water infiltration issues.
Get In Touch with Tule
Harnessing the power of Tule sensors has revolutionized our irrigation practices on our family farm. The insights provided by the Actual Evapotranspiration data have been crucial for effective water management. By focusing on the ETa values, we have gained insights into issues affecting orchard productivity and we have increased yields. I encourage you to get in touch with the Tule team so you can see similar gains at your operation. Click here to speak to someone at Tule.