Southern Marsh Orchids

Southern Marsh Orchids

Wednesday, 27 January 2016

Baffled, of Cwmbach

A few days ago, I took a stroll up the lane behind our street, looking for microfungi to try and identify. Passing some shaded Cherry Laurel, I noticed what I took to be an algal coating on their upper surface and with almost no hope of an identification, I collected a specimen.

At home, I moistened the coating and carefully scraped some off to mount on a microscope slide. Even under low power, I could see what looked like dark awl shaped hairs sticking up from the surface of mass of algal cells. At first I wondered whether the hairs could have come from the leaf itself, even though I wasn't aware that Cherry Laurel leaves had any. A quick check of a portion of the leaf without the alga revealed absolutely no hairs, so I am left with the conclusion that the apparent hairs are in some way connected with the alga.

I doubt whether I will ever find out what the alga is, assuming it is and alga, and I am not fishing for an identification, but does anyone know what the 'hairs' are and what is their function?

Presumed alga, with hair-like features. 200x

400x. Each division of the graticule represents 2.50 microns.


  1. I haven't a clue what these things are but I vaguely remember seeing an image similar to these in a magazine/journal - some form of fungal disease with a name similar to anthrax nose .... sorry, but that's the sort of thing that my dustbin of a brain remembers!

    I've just done a google search and it suggested 'anthracnose' which is caused by something called Colletotrichum and that's where the image I saw comes in. Hope that means something to you

  2. Well done Howard, you might be onto something there. I've never seen anything like that.

    Figure 5 at the following link looks similar:

  3. Thanks to both of you. I've heard of Willow Anthracnose: it has been killing the riverside willows (S. alba x S. fragilis, I think) around here for over twenty years. I wonder what anthracnose it is and what it is infecting, in this instance? Time for another look, I think.