red band needle blight
Dothistroma septosporum
A fungal disease of the Ascomycetes attacking the leaves of conifers, mainly pines. Its native range is unknown. Older needles and those in the lower crown show symptoms first. Spots and bands appear during the growing season which soon turn red, and the ends of the needles then die back. Eventually, as the disease progresses, only the recently infected current-year needles remain at the branch ends, and repeated attacks weaken or kill the tree. Until the 1990s the disease was most damaging in the southern hemisphere and was rare in Britain. Since then it has spread rapidly in Britain, associated with warmer and wetter springs and wetter summers.
This definition is abridged from A – Z of tree terms: A companion to British arboriculture.
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