Missing Ingredient: Almond growers unknowingly lose yields because of a lack of boron

摘要

ASKED what the most common nutrient deficiency is in almond orchards, many growers will respond that it's nitrogen. Still others might answer zinc. But while those are the two most commonly applied nutrients, the most prevalent deficiency in almonds is actually boron (B), says Roger Duncan, a University of California pomology adviser in Modesto, CA. Duncan's not surprised that most growers don't have the correct answer, because in almonds, boron is elusive. The big problem is that a deficiency of boron, unlike other nutrients, is not readily visible. Unless the deficiency is unusually severe, it can't be detected with a visual examination of the tree. The only impact of a moderate boron deficiency is perhaps the most insidious of all — declining yield.