Almond

{Prunus amygdalus}

Boron deficiency in almonds

When almond trees are deficient in boron, the young branches die back from the tip, and the development of shoots from near the base of the branch gives a “witch’s broom” effect. Other symptoms include:

  • Poor nut development
  • Premature fall
  • Nuts turning yellowish and may later blacken
  • Brown gummy areas in the nuts extruded on the surface

U.S. Borax, part of Rio Tinto, is a global leader in the supply and science of borates—naturally-occurring minerals containing boron and other elements. We are 1,000 people serving 650 customers with more than 1,800 delivery locations globally. We supply around 30% of the world’s need for refined borates from our world-class mine in Boron, California, about 100 miles northeast of Los Angeles. Learn more about Rio Tinto.

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