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Almond Facts
MARCH | APRIL 2015
TIME TO CONSIDER
increase. This yield reduction is due to the osmotic effects of the salts, which basically makes the tree “work harder”
to uptake water, reducing growth and vigor. If excess salts continue to accumulate within the rooting zone, trees will
ultimately uptake the salts (mainly sodium, chloride and boron) and cause tissue toxicity. A leaching program should
be implemented when EC of the entire rooting depth exceeds 1.5 dS/m or sodium, chloride and boron exceed an
exchange saturation percentage of 5 percent, 5 meq/l and 0.5 mg/l, respectively.
Remove Cover Crop
When managing severe drought, vegetation on the orchard floor should be eliminated. Depending on the coverage,
cover crops may increase water usage by as much as 30 percent. Keep in mind that cover crops do provide soil health
benefits and should be replanted when water is available.
Maintaining micro-irrigation systems and application timing. Maintenance should be performed on systems to increase
the distribution uniformity. This includes flushing and replacing of lines, irrigating in smaller sets to maintain pressures
within the operating range, and matching water application rates with soil intake rates. Sets should be no less than 6
hours and should be completed in the cooler, calmer part of the day.
Minimal Impacts of Anti-transpirants
University of California research has not been able to document water savings or reduction of plant stress with
the application of anti-transpirants, or “plant coolants,” and thus they are not recommended. Many new products,
however, enter the market annually, and there is always the possibility that some may prove to be of benefit. When
applying these products, it is important to leave several untreated areas in the field in order to determine product’s
effectiveness.
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