Figure 4.28 Transverse section of ectomycorrhizas showing labyrinthine Hartig net hyphae (arrows) in roots of Pinus sp. (left) and Populus sp. (right). Fungal hyphae are structurally modified, making intimate contact with root cortex (C) (left) or epidermal cells (E) (right) and enabling exchange of resources through the interface between fungus and host. A mantle of fungal hyphae (M) surrounds both roots. (Photographs courtesy M. Brundrett)