Jump to content
Sign in to follow this  
David Humphries

Rigidoporus ulmarius

Recommended Posts

Rigidoporus ulmarius;

common bracket found on Willow, Elm and Horse Chestnut.

Sometimes mistaken for 'Perenniporia fraxinea' which favours Poplar, Elm and Ash.

Both have perenial brackets.


Although niether are on the Red data list of threatened brittish fungi,

P. fraxinea is thought to be somewhat rare.


The easy way to distinguish the difference, is when you cut a slice out.

P. fraxinea has flesh and tube layers of the same colour. Whereas Rigi has orange fading tubes which contrast sharply against the spongy white flesh.


Green algal and/or moss growth on the top surface is pretty typical.


Decay type is Brown cubicle rot.



Here are three Rigidoporus brackets hosted on Horse Chestnut.







Edited by Monkey-D
Decay Type added

Share this post

Link to post
Share on other sites

Slices showing the orange tube layer of Rigi' and the buff spongy flesh.

This layer can be between 1 and 5mm deep.








Edited by Monkey-D

Share this post

Link to post
Share on other sites

Underside showing pores.


Apparantly there are 5 - 8 per mm. But that's getting far to anal. :blushing:

Be wearing a lab coat and geeky specs next, :001_tongue:





Edited by Monkey-D

Share this post

Link to post
Share on other sites
Tom D   

According to my instructor on the PTI its quite rare up here, I've never seen it, he also said If you find one he'd like one for the class. Perhaps you could make money selling them to scottish colledges.:001_tongue:

Share this post

Link to post
Share on other sites

I know of a Rigidoporus bracket within the cavity of an ancient Yew. Havent seen or heard of it on Taxus before.

Share this post

Link to post
Share on other sites

Just adding to the records...


Found 04.03.09 on its eponymous host (in this instance Ulmus procera)at the union of a major limb extending over a busy A-road. A proper inspection perhaps with some decay detection equipment will inform any reduction works.



Share this post

Link to post
Share on other sites



Good thread as have been struggling between the two. Ok so I think I know of a good size R.ulmarius bracket under a large limb on a chestnut in a local park (Will take pictures Monday). The limb is over a busy path in the park. As it’s a brown rot I would say it would be good to reduce/remove the limb pretty soon?


Cheers Steve


ps heres some pics I took a while back of i think R.ulmarius on a chestnut stump?





Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

Sign in to follow this  

  • Featured Adverts


Arbtalk.co.uk is a hub for the arboriculture industry in the UK.  
If you're just starting out and you need business, equipment, tech or training support you're in the right place.  If you've done it, made it, got a van load of oily t-shirts and have decided to give something back by sharing your knowledge or wisdom,  then you're welcome too.
If you would like to contribute to making this industry more effective and safe then welcome.
Just like a living tree, it'll always be a work in progress.
Please have a look around, sign up, share and contribute the best you have.

See you inside.

The Arbtalk Team

Follow us

Get in touch

facebook feed

Recent tweets