Monday 13 January 2014

Paxillus Involutus (Rollrim) fungus

Paxillus involutus (Roll rim) fungus

This is a large agaric that can grow either in trooping groups or is solitary.  It usually can be found in broad-leaf woods near to birch and on acid soil.

The cap can be up to 12 cm and it can be tall with the stem measuring up to 7 cm.  Initially the cap can be olivaceous and as maturity happens it will become more hazel-brown, firstly convex, then becoming expanded and somewhat depressed in the middle.  The margin will be in-rolled.  The gills become sienna-brown with rust spots, decurrent and crowded.

The stem is concolorous with the cap.  It is distinguished by darker bruising at the apex of the stem.  There is no ring.

I came across my first P involutus on a day trip to Stanage Edge in the Derbyshire Peak District.  Stanage derived from stone edge, is famous for rock climbing.  It has an elevation to 1,503 feet at its highest point.  It was historically a paved packhorse road which ran along the top of the edge.

We walked across the ledge on a crisp and very windy October day.  Silent except for the wind and the chink of metal from the rock climbers.  We took a path downwards to Curbar Wood. a magical wood empty except for us.  During that lovely walk I came across huge groups of Fly Agaric.  The P involutus was solitary in a little clearing next to birch trees.  It is a handsome fungus.  The one I photographed had an extremely prominent umbo.  I have subsequently been told that this sometimes happens, and then it becomes depressed.  It is easily recognised by the decurrent gills which stain darker brown at the apex of the stem.

Also on this trip I think I came across Beech milkcap (Lactarius blennius).  The cap had a white droplet of milk visible at the margin edge.  The cap is 4-10 cm across and the colour is very difficult to describe but being a mixture of olive, grey, green and even silver.  The texture of  the cap reminded me of unfired Denby pottery, which is interesting as it is a pottery based in Derbyshire!

Thank you to RE for taking me to this lovely area of Derbyshire/S. Yorkshire.

These photographs can now be seen on,  Browse 5.