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Cross section of a tree trunk.
(Andri Eloff, Wnyboer
) |
Ash trees are considered ring-porous, which means that their vascular vessels are relatively large and concentrated directly under the bark. This characteristic makes ash trees especially vulnerable to attack by EAB larvae, which restrict their feeding to tissue in the ash tree’s cambium layer.
The vascular systems of diffuse-porous trees, such as birch, are characterized by vessels spread evenly throughout the sapwood. |
