Friday 23 September 2011

Fungal season

Fungi are popping up everywhere, so it's time to get the microscope dusted down, ready for the new season.

The mushrooms that we see are the visible fruit-bodies of the actual fungus, which is usually underground or buried deep inside some substrate, such as wood. The fungus itself will stay in the same place as long as its partner or food source continues to be available: that explains why a particular mushroom can continue to be found in exactly the same location year after year. I'm now beginning to expect my usual crop of Phaeolepiota aurea on the same spot on my lawn at the same time every year. This is a rather scarce mushroom, which is thought to be a nettle associate:

Phaeolepiota aurea
At the beginning, the underside is completely sealed, providing a secure environment for the spores to develop:
Phaeolepiota aurea

Later on, the seal drops to form a ring and the millions of spores are released to be carried by the wind.

Recent studies on Phaeolepiota aurea have confirmed that compounds of cyanide remain in the mushroom, even after cooking, so it has been added to the list of 'poisonous' fungi.

I have previously written about the structure of lichens: fungi which have captured algae in order to utilise the energy that the algae can generate from sunlight. Essentially, lichens cannot survive alone: they need their algal partners to supplement their food supplies. What is particularly interesting, however, is that some fungi can be part-time lichens: most of the time, they survive on their own food resources, but they can capture algae on a temporary basis in order to survive transient periods of hardship. A number of fungi can do this, but it is the Omphalina family which is best known for it.  Omphalinas are small, delicate, trumpet-shaped fungi that are associated with mosses. This specimen is about 8mm. across the cap:

Omphalina griseopallida

I know of a few Omphalina species in my area (we have lots of mossy locations), but this one is new, and looks most like Omphalina griseopallida. I'm taking a spore print to see if that helps with the identification.

Spore prints are one of the basic tools in identification of fungi, and the spores of some species give very strong clues about an identification. This is the spore print of a new species to me: Stropharia aurantiaca.

Spores of Stropharia aurantiaca at x400

Stropharia aurantiaca is a relatively recently-named (1930's) fungus which appears in bark and sawdust that has been used as a top-surface mulch on flowerbeds. In this case it's in a local supermarket car park It has been found numerous times in Northern Ireland, but I can't find any previous records from Ireland.

I'll try to get an in-situ shot later today.

2 comments:

Gerry Snape said...

thankyou for the post about fungi. perhaps I could ask you to pop over to my blog about those in my field here in the N.W. and give me an idea as to what they are as I've never had quite so many as this year. Is it an exceptional year for fungi? or have I just not noticed them quite as much as this time. Thankyou.

The Weaver of Grass said...

Fungi seem to have been very prolific this year where we live Stuart. Maybe the weather has been just right.