A network that helps people worldwide obtain rapid advice and information on crop protection, including the identification and management of plant pests.
PestNet is a network that helps people worldwide obtain rapid advice and information on crop protection, including the identification and management of plant pests. It started in 1999. Anyone with an interest in plant protection is welcome to join. PestNet is free and is moderated, ensuring that messages are confined to plant protection.
October 2003. New Caledonia reported the death of Jackfruit and Lychee trees close to a forest (photo, lower left), and suspected that they had been killed by Armillaria. The photos were not helpful in making a diagnosis. There are other root rotting fungi that could have caused the deaths, Phelinus and Ganoderma, in particular.
However, a member sent two photos of Armillaria to PestNet (those above) to give an impression of what the fungus looks like and also provided some notes on how to diagnose the fungus.
When the roots and trunk are cut open is there a white mycelium between the bark and the wood? (sign for Armillaria, see attached image for Armillaria luteobubalina in Australia). Also, is there a seasonal production of olive-yellow mushrooms around the base of the tree that have a ring around the stipe, gills attached and white spores? Otherwise you may have a Phytophthora attacking the roots which will need to be analysed in a laboratory to make the identification.
Later (May 2011), On re-examining the image (lower), it seems that there is an old bracket on the side of the tree belwo the arrow. This could be Phellinus or Ganoderma (Editor).