As you may know, monitoring and minimizing plant stress during postharvest is one of the most important things you can do to ensure fruitful future yields. Using Tule’s FieldStat, you can monitor the crop stress of your field daily and remotely during this critical time. Below, we quickly review the effects of water stress for each growth stage of almonds, as supported by current academic research.¹

• Early Season
  In general, stress should be entirely avoided during the early stages of the season (specifically from leaf out until the onset of hull split, including nut set). During early season canopy growth, any stress-induced water deficit will hamper photosynthesis and limit growth. This will have direct, negative effects on current and future yield. During the subsequent period of nut set, any significant water deficit will lead to increased nut drop and smaller kernel size.² (Tule recommends Target FieldStat set to Low Stress)

• Hull Split
  From the beginning of hull split until 90% hull split, research indicates that moderate levels of stress may help conserve water and have only negligible effects on yield. Specifically, maintaining a midday stem water potential between -14 and -18 bars has been shown to decrease total water consumption by 15% without affecting nut size or total nut load.³ (Tule recommends Target FieldStat set to High Stress)

• Pre-Harvest / Harvest
  Following hull split through harvest, it is critical that you irrigate to maintain as little stress as possible. During these phases, water deficits will result directly in decreased nut weight and quality.⁴ (Tule recommends Target FieldStat set to Low Stress)

• Postharvest
  During this stage, the buds for next season’s nut growth begin to set and develop; water stress here has been proven to have a greater effect on yield than any pre-harvest deficits.⁵ (Tule recommends Target FieldStat set to Low Stress)

With Tule, you can easily and remotely monitor your crop stress over an entire field to ensure irrigation doesn’t limit yield potential throughout the season. Tule allows you to track your performance as compared to the research above by setting different stress targets for each phenological stage. With your targets set, Tule will alert you if your crops exceed your stress threshold and provide an irrigation recommendation to get you back on track.

To learn more about tracking strategic deficit irrigation and irrigation management with Tule, please contact us.

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1. For more detailed information on various SDI techniques please see the California Almond Board’s guide.
2. Prichard et al. 1996; Lampinen et al. 2007
3. Shackel et al. 2004
4. Goldhamer and Viveros 2000
5. Goldhamer and Viveros 2000