Fungus on Birch twig?

[JennyS]

I think this must be a fungus as it doesn't look right for lichen apothecia, sorry about photo quality but I'd be interested to know what it could be.

Seen today, very abundant on live Birch twigs, but it didn't seem to be present on the larger twigs or branches. Twig in the photo is approx 2mm diam.



Help appreciated,
Jenny

[watsthat]

Hi Jenny

I`m just speculating really, (in the absence of any other replies), but the growths in your pic look a bit too regular. Could they be some kind of insect gall? You might get a response on the Insect Forum.

Cheers

Pete

[mollisia]

Hello Jenny,

have there been only twigs with ball in that colour, or have you also seen twigs where those balls were pinkish? My thought is, that this might be an old Tubercularia, the conidial form of Nectria cinnabarina.

best regards,
Andreas

[JennyS]

Hi Andreas,

They were only that colour and appeared to be only on the small, peripheral twigs.

My first thought from a distance was that it might be Coral spot on dead twigs, but looking closer the twigs were still living and there was no sign on the tree (a very small ornamental Birch) of pinkish growths.

Jenny

[healfdan]

From your photograph it looks like it could be scale insects Pulvinaria sp.

[JennyS]

Thanks Pete and healfdan, I've posted the photo in the Insect forum.

Jenny

[JennyS]

My thought is, that this might be an old Tubercularia, the conidial form of Nectria cinnabarina.

Thanks Andreas, that seems to be the most likely explanation