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AlmondBeat #5: Optimize hull-split with our algorithm. Just ask your trees

Updated: Jul 13, 2021

Hull split is around the corner in California and the northern hemisphere and growers need to apply strategic deficit irrigation, to achieve better uniformity of hull-split through each tree. An optimized hull-split process can also reduce the impact of navel orangeworm (NOW) d the costly spray programs required to manage it.

Our hull-split algorithm is here to help growers do just that.

AlmondBeat #5, here we go.

Preparation starts in Spring

Uniformity of hull split throughout each field/block improves quality and brings many operational benefits; less re-shaking and better utilization of harvest and processing assets. A primary reason for poor uniformity at the block level is poor irrigation decisions during the season that lead to excess water movement to low-lying areas. Phytech provides confidence throughout the season to reduce the irrigation, either volume or duration, whenever possible so there is less drainage to the lower parts of blocks where delayed hull split becomes an issue. The benefits of this are available in the first season but most growers report a continual improvement over subsequent seasons. So, irrigation decisions during spring and early summer affect hull split uniformity across a block, but as every almond grower knows, uniform hull split throughout a tree is rare to see. But could it be better?

Less is more - the benefits of deficit irrigation

Inducing mild to moderate daily stress patterns on the almond tree during late June and July, dependent on season, maturity level and variety, is the best way to improve hull-split uniformity, help with crop removal and facilitate a slightly earlier harvest. The longer those open nuts hang on the trees - the longer they're susceptible to damage and hull-rot. Another benefit is that drier fields are more easily accessible by large harvesting machinery.

Walking a tightrope

By reducing water delivery and applying stress the tree needs to draw water from the hull. When water leaves the hull, back through the tree, the split occurs. Now comes the hard part: how to control this deficit strategy?

Apply too much stress, or cumulative stress over multiple days, and the uniformity of the hull split throughout the tree will be poor. The hulls at the top and outer edges of the tree will open further and sooner than the hulls lower in the tree and further inside the canopy.