This picture, care of Dave Bidwell, shows a tree severely infected by Armillaria
Out walking in Lane Cove National Park yesterday I noticed lots of fungal fruiting bodies - toadstools of brown, red, green and blue hue. To remind us why there are so many around, it rained during the walk.
So now is the time to find out what fungal hyphae are lurking beneath your garden soil. The toadstools and mushrooms are of course the tip of the hyphal iceberg. Most plants needs fungi to survive so don't be too distressed to see the occasional fruiting body in your garden. However some of course are a big problem.
Just this week our head Arborist at the Royal Botanic Gardens, Dave Bidwell, sent out a reminder to us all to be on the look out for Armillaria Root Rot. As Dave said: "fruiting bodies of the fungus Armillaria luteobubalina are in evidence at present at or around the base of trees across the estate. Armillaria is a pathogen which can kill large trees, but sometimes acts as a saprophyte living off dead material. It is difficult to control...'
Dave included some photos with his email and I've included one of them here. It's a spectacular example on an Erythrina. The picture was taken last year and tree has since died and been removed.
Our Plant Pathology team is keen to map the distribution of the fungus in the Gardens so that we can limit its spread and work on local control measures.
As I told my walking companions yesterday, Armillaria (like all true fungi) is more closely related to us than it is to flowering plants. This doesn't really make any difference to the way we treat it but perhaps it's due a little more respect? Or maybe less if you are a botanist?