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When trees get sick

Pathogens, epidemics, and the diversity that decides whether a woodland survives one.

Growing·Restoration·Trees·Ecology
  1. 01
    Bark lesion and crown dieback on a mature broadleaf tree
    Trees№ 4946 min

    Tree Diseases: The Pathogens Behind the Dieback

    Fungi, bacteria, oomycetes and the named epidemics reshaping temperate forests, plus how to diagnose, contain, and design against them.

  2. 02
    An ash tree with characteristic pinnate leaves and thinning crown showing early dieback
    Trees№ 0205 min

    Ash: The Tree We Are Losing

    Light canopy, superb timber, and the fastest-moving tree disease in Europe — plus why the survivors matter more than anything else in the woodland.

  3. 03
    Young elm suckers growing in a hedgerow with the stump of a mature tree behind
    Trees№ 1525 min

    Elm: The Ghost in the Hedgerow

    A tree that lost its canopy to a beetle-borne fungus but never quite died — surviving suckers, resistant cultivars, and the butterfly that depends on it.

  4. 04
    Close-up of bark beetle galleries visible under tree bark
    Growing№ 2294 min

    Tree Pests: Identification, Prevention, and Natural Control

    Identify and manage bark beetles, termites, and root grubs through integrated pest management, healthy soil, and natural predators.

  5. 05
    A vertical cross-section through a mixed oak woodland showing ground flora, shrub layer, understory, and canopy
    Ecology№ 4685 min

    Structural Diversity: Layers Equal Niches Equal Species

    Ground cover, shrubs, understory, canopy, emergents. Each vertical layer doubles the species count. Design for layers.

  6. 06
    Mixed-provenance young trees planted in a trial block on a drought-stressed slope
    Restoration№ 0886 min

    Climate Adaptation: Planting for the Weather That Is Coming

    Provenance shifting, assisted migration, and designing for variability rather than a new average — plus the arguments against moving species around.

  7. 07
    Labelled seed envelopes and glass jars of dried native tree seeds in a community seed bank
    Restoration№ 4185 min

    Seed Banking: Preserving Genetic Diversity

    Collect, dry, and store local provenance seed to preserve genetic diversity and supply restoration projects with well-adapted planting material.

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