Juniper black fungus

Anyone have any idea what this is and if so how to eradicate it? It appears to be a black fungus-like growth coming out of areas of abnormal tissue swelling on the main trunk and primary branches of a juniper. The swellings were already present when I got the tree but the black growth has only appeared in the last week as temperatures have started to increase. It appears to be exposing cambium as it splits apart.

I am UK-based in terms of fungicides etc

Google ‘Cedar Apple Rust’. Those black areas will turn to orange jelly following rain this month and release their spores to inter act with hawthorn/apple etc. depending upon variant. It’s fairly rampant in certain parts of the UK. I’ve been fighting a very small dose of it in recent years .with Mancozeb and Lime Sulphur…Am also planning to use a product from Probio Carbon on the tree this year…

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Hey Blown, think I found a previous thread that you contributed on regarding this…thanks for the advice mate! Is it acceptable to keep this tree, remove the infected areas and then begin the cycle of spraying junipers and fruit trees to help prevent further infections?

This is what I and a few friends do. When I first found the issue it was possible to cut out a few twigs from the juniper without ruining the tree. I had spotted some damaged leaves on a hawthorn the previous season which had been eradicated. In one area of the juniper the fungus was on the trunk and so impossible to cut out. I physically removed it with a scraper before it turned to jellies. Now waiting to see if I gat e repeat this season. I used Mancozeb at appropriate times of year along with 2 Lime Sulphur washes at start and end of winter. I still refuse at this stage to burn the main culprit but I do keep a very careful eye on my trees.

PS. I know that some people in mainland Europe have huge issues with this and in some cases local tree populations have meant that they just can’t beat it.

I think this may have come in with this tree as I haven’t previously had problems with my other junipers. Mine has a larger canker on the trunk so was thinking of creating a Shari at that point. Do you have to go deeper than the xylem to cut it out or does it just exist in the phloem and cambial layer? Goddamn fungus!!

If you can stop it sending spores out and then no alternate host carries it through summer you could be winning. The spores release from hawthorn/apple back to juniper at the end of summer. Google will show you what to look for on their leaves.

thanks man, unfortunately when i set about removing all the affected pieces it turned out that almost every single primary branch had cankers on resulting in almost all of the foliage being removed, and i would’ve had to reduce the live vein by around 85% so unfortunately the tree has gone. Damn shame as it was a really nice piece of material and would’ve made a lovely bonsai!! Thanks for the advice though, appreciate it!