endomycorrhiza

One of two kinds of mycorrhiza, sometimes called arbuscular or vesicular-arbuscular mycorrhiza, whose hyphae can penetrate root cells to form tree-like branching systems (arbuscles) that increase the surface area of the root system for the exchange of water, nutrients and metabolites.

This definition is abridged from A – Z of tree terms: A companion to British arboriculture.
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