black ooze

[bobby]

you see a lot of this stuff but can anyone tell me what it actually is/causes it?

black, tar like substance coming out of an old pruning wound.

is it just moisture and general dirt/sap? or something more sinister?

cheers

[Stuart A-C]

Bleeding canker is an infection of the bark of several trees by a number of different species of the fungus-like micro-organism Phytophthora, causing the affected bark to bleed a dark sticky fluid. Cankers may be present at any time of year.

 

Trees commonly affected in the UK include Aesculus (horse chestnut), Tilia (lime) and Alnus (alder).

 

Horse chestnuts continue to be affected by Phytophthora bleeding canker at a relatively low level, but have recently been affected by a huge upsurge in cases of bleeding canker caused by a bacterium.

 

Holly is affected by Phytophthora ilicis, which is more commonly the cause of leaf blight but can also infect bark, causing cankers.

 

Alder is affected by the newly described P. alni, which has been shown to be a new species formed by the hybridisation of two other species, neither of which affects alder. This is a worrying development and spread of the disease is being monitored by Forest Research scientists.

[Stuart A-C]

That was copied and pasted from the RHS website.

I have seen it starting to appear in a few oaks down this way recently, and when in Leicester we had to fell a few very mature oaks with it

http://www.charnwood.gov.uk/news/2008/03/07/scientists_investigate_charnwood_oaks

Edited December 4, 2009 by Stuart A-C
added link

[bobby]

thanks for the reply. can you be sure thats what it is from that photo though? might it not just be bat turd? is there a simple way of testing what the cause of it is?

thanks

[White Noise]

A bit off thread . Your avatar is mint .

[David oakman]

If you can see holes higher up the trunk then yes it may well be bats. The bats will live higher and the droppings drop down get wet and run out of small holes as in your picture.

[bobby]

same tree. opposite side. about 4 metres up