To be most effective current treatments depend on the earliest possible discovery of a rot by an experienced person (or a trained sniffer dog). Rapid confirmation that a rot is honey fungus is usually possible only if a number of rhizomorphs have developed around and on a host, but these are usually seen only in the later stages of colonisation by Armillaria mellea. As rhizomorphs are not always evident, conventional identification techniques entail the isolation of the fungal mycelium present in rotten roots on to agar. This takes longer to perform than methods based on immunology or necleic acid sequence variation. Nucleic acid hybridization techniques are being evaluated experimentally for rapid diagnosis to aid investigations to assess whether chemical or biological control methods are appropriate. Such control methods are described and the prospects for a management strategy that combines diagnosis and control of virulent species of Armillaria in amenity horticulture are discussed.
