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Manion spiral model

C0896d5f89505679e917b22abe81f240?s=47 Forest Research
December 15, 2017

Manion spiral model

Chronic oak decline


Forest Research

December 15, 2017


  1. 15/12/2017 1 Decline Spiral Model – evolving concepts Bacteria The

    Decline Spiral Model (Manion, 1981) Decline: Arises from factors that interact sequentially or simultaneously and have a cumulative effect over time. Certain factors may have key roles. Predisposition/altered host condition probably essential. Root health Secondary pests and diseases are of primary importance in causing tree mortality Wargo, 1996