Unidentified fungi and lumps in leaves on Plum Tree

Hi, this is my first post. After a near miss when a branch came down (we bought a house three months ago), I've examined the plum tree and found fungi of two possibly different species and strange bumps in the leaves. Also the fruit was rotten on the branches in March, and my experience (though limited) is that healthy fruit falls off.

I've tried to attach images to this post, there are better captions and a description at my blog Plum Tree - neglected, bodged, fungi and disease. | The Bodged House



These do not appear to penetrate the bark,



These were found below the fungi above and appear to be of a differing species



Strange lumps on the leaves.



Last year's plums are still on the tree and I remember them appearing rotten with white fungus in little spots during the winter.

 

Lumps on leaves

My tree has exactly the same lumps on leaves... I hope someone can help identify the disease, I'm looking forward to making plum conserve this year

 

Good evening Philip and welcome to the site. The fungus is a type of Bracket fungus, harmless to you and the tree. The other problem looks like a type of rust. will investigate further.

 

The problem with the plum fruits is brown rot and they should not be left on the tree. They really need to be removed and binned/burned. The spores of the fungus are spread from the decayed fruit to the new ones, so you may well have a problem with it this year.
We have the bumpy leaves on our wild plums. I did find out what it was last time, but for the life of me I cannot remember what it was. There is no mention of this in the Buczacki and Harris book.

 

Just had a look at some of these leaves and there are tiny and I mean tiny green/yellow insects on the ones with the 'galls'. I have a feeling that these are the trees reaction to these insects.

 

Hi Philip_Clarke

The bumps on the leaves are caused by leaf-munching insects making a home in the space between the lamina or leaf surfaces. They'll probably lay young in there too, so you may want to prepare for an invasion in the near future. The bugs don't cause any serious damage other than defoliate the tree, which may lead to a loss in photosynthesis and food production, but this is a contested issue and your tree may fully recover next year.

A more important issue is the fungus.

Personally I feel this is erroneous advice and should not be acted upon.

As you rightly point out the tree may have up to three species of fungal infection. Unfortunately, from the pictures I can't really identify them properly, but one of them looks like Ustulina deusta, a particularly nasty parasitic fungus that munches its way through the tree's heartwood, leading to eventual failure (depending on the tree's natural fungus-inhibiting capabilites).

The fungal brackets on the tree are simply the fruiting bodies of the fungus proper - they release millions of fungal spores that germinate into new fungus, similar to the way a tree produces seeds in order to reproduce. Unfortunately, once these fungal brackets appear on a tree the actual fungus (which is a collection of cellular strands called hyphae that live within the tree's cells) is already well established and causing all sorts of mischief.

The rotting pears are another fungal infection, and they need to all be removed and destroyed, especially if there are other fruit trees in the vicinity.

I think your tree is in for a tough time as it seems to be getting attacked from all angles at the same time, but, depending on the tree's vigour, it may be able to battle on, although I would definitely recommend keeping a close eye on it and having it annually assessed.

Hope this is of some help.



Matthew