Sunday, 27 November 2011

Spot of bad luck

I took a quick spin round Drumboe woods and found a few things worth noting.

This is a good time of year to find mines of Ectoedemia sp. micromoths in 'green islands' in fallen Oak leaves: the leaves you want are quite easy to identify due to the green part contrasting with the brown of the fallen leaves. These micromoth larvae extend their feeding season by blocking off the chlorophyll return valves in the leaf. This ensures that a supply of food continues to be available even after the leaves have fallen from the tree. The specimen shown below had a bit of bad luck, however:

Ectoedemia micromoth mine in 'green island' in Oak leaf
The mine starts at point A (near the midrib and on a sub-vein of the leaf) and follows the sub-vein for a while before beginning its blotch mine at point B. This is all normal procedure and has so far worked well for the larva. Unfortunately, the point chosen for the blotch happens to be exactly at a place where the valve-closing has failed, and the chlorophyll is gone, making that part of the leaf useless as food. The mine has been aborted at this point, probably because the larva has starved. Leaf-miners follow some fairly complex rules when making their mines to help ensure that:

  • they don't fall out of the leaf
  • they end up at a part of the leaf that contains enough food for their growth and development
  • the mines don't cross themselves, which would force them to encounter (and eat) their own dung

Some of the rules involve following veins, others force a change of direction after a certain amount of time; other decisions are made by the female when she lays the egg. The rules don't always work, but I find that the vast majority of mines are successfully completed. I'm guessing that in this case the rule to turn away from the sub-vein is timed and the location was just plain unlucky.

You can see a normal mine here:

I found a few fungi including this Clitocybe vibecena:

Clitocybe vibecena
And a very gone-over Scleroderma citrinum earthball, resembling nothing so much as a piece of orange-peel:

Scleroderma citrinum earthball
Earth-balls disperse their spores by breaking down the outer surface, enabling the spores to be wind-distributed. The outer crust of the fungus is conveniently structured with fragile fissures which make this break-down much easier.

Even dead and now-useless parts of plants can have innate beauty: this empty seedhead of Hogweed was worth photographing:

Hogweed seedhead

Sycamore leaves are covered in their tar-spot fungus Rhytisma acerinum:

Sycamore tar-spot fungus, Rhytisma acerinum
As usual, this fungus is spread by wind-born spores. Notice that most fungi try their hardest to maximise the area available for spore production: the surface of the fungus is wrinkled and domed.

We have had solid rain for the last two weeks and I haven't seen a single moth in that time. The last night, in pouring rain, a single specimen of Red Sword-grass came to light. The Red Sword-grass hibernates as an adult, so something must have stirred this one from its hiding place.

Red Sword-grass
 Red Sword-grass has a mostly western and northern distribution and is found mostly near bogs or heaths.

Sunday, 20 November 2011


Timing is very critical for our wildlife. Leaf miners need leaves which contain enough fresh green matter to keep them fed until they mature, so they can only exist in summer. Flowers need flying pollinators to transfer pollen from one plant to the next. Birds need caterpillars to feed their young. Sawflies need fresh leaves for their larvae to feed on. Frogs need warm water for their tadpoles to develop. Parasites need their target species to be present before they can be parasitised. All species need their pre-requisites to be in place in order to feed/pupate/hibernate/survive.

Some of these timings are pretty relaxed. For example a bird can find larvae of suitable species for all of the breeding season, which might be all of 6 months long. But other timings are much more critical. If you consider that many mushrooms exist for only a few days, then any dependant larvae must grow from egg to maturity in that same short timeframe. Taking that further, any parasite that needs the larva to be present must also be around during those few short days: their opportunity to parasitise might be as short as 2 or 3 days in a year. Synchronisation is crucial.

When I was considering all of this, I noticed a specimen of Lawyers Wig - Coprinus comatus - on my lawn. I know that these tend to last perhaps 48 hours at a maximum, so I thought I would try to capture the life and death of this specimen over time.

I set up a platform for the camera and took shots every 2 hours. Sadly, the days are very short now, so I didn't get as many shots as I wanted. I should also point out that lying in very wet grass for even short periods is not a pleasant experience.

This is the shot at 11am:

By 2 pm. things had moved on a little:

And by 4 pm the light was fading and I got this shot:

Next morning only the stipe (stem) was left.

The Coprinus family of fungi reproduce by liquidising the spore-bearing gills, dropping the spores very locally (and very quickly). This is a double-edged sword: the spores don't get distributed very far, but there is also very little time for a hungry larva to consume any of the spores.

Timing is again of interest in this shot of the December Moth:

December Moth
I took this shot on 16th November, which is two weeks before December. It is well documented that this moth now appears from late October until January, but it must have originally been named December Moth for a good reason: it appeared in December. Phenology (the study of timings of appearances of species) shows that species are appearing at times which vary from the recordings when the species were named 2 or 3 hundred years ago. This applies mostly to plants and insects, but bird migrations are also changing. This variation in species timings is one of the reasons that global warming was detected: it might not tell us why we're warming up, but it certainly confirms that it's happening.

Wednesday, 9 November 2011

Sun, light

The weather has actually been quite reasonable since the start of November, with a few bright days. Early sun after a chilly night leads to only one thing: dewdrops on plants. So I grabbed the camera and went out to see what I could find.

I like the way that dewdrops act like tiny lenses, magnifying whatever lies behind them:

Dewdrops on grass leaf
 The drop on the end of the leaf on the right caught my eye:
Dewdrops on grass
Here's a close-up:

Dewdrop as a lens

Spider's webs and mosses also catch the water:

Polytrichum moss with water droplets
(Notice the new capsule forming to the right of the picture).

The forestry was a bit damp, but I found this fascinating mushroom growing on moss on a piece of Spruce bark left over from the harvesting a few years ago:

The size (15 mm across the cap), shiny cap and domed appearance immediately made me think of Panaeolus, and the gills were suitably grey, but the yellowish stipe (stem) didn't fit with anything in the books. I took a spore print, fully expecting to find a black spore deposit, and was astonished to find that the print was white. Back to square one. Repeated keyings led me to Mycena, but I had never seen a Mycena specimen like that. Suddenly I remembered Mycena epipterygia, which I have often found nearby, and which has a stipe with a pronounced yellow base and yellow top. It seems that this specimen, which was a good deal larger than usual, had dried and had perhaps also been slightly frosted. Every day has a surprise.

I also found a single specimen of Crepidotus variabilis on a fallen twig:

The big surprise about Crepidotus is that they have brown spores, and there is a hint of this under different lighting conditions:

Crepidotus showing a slight pink in reflected light
Crepidotus in slight light
Crepidotus in setting sunlight
I think fungi can be extremely beautiful if you look at them closely.