MOST COMMON NUTRIENT DEFICIENCIES IN VASCULAR …

Secondary xylem is produced within the vascular cambium, and new layers of xylem are deposited around the old layers. As a result, the older layers of xylem are not damaged. Secondary phloem is deposited outside the vascular cambium. As the tree gets larger in diameter, the secondary phloem is crushed, stretched and continually replaced. ................
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