Saturday, November 03, 2018

Autumn 2018

Quite a few new things this autumn.  In Medlar Wood, now more open than in earlier years, wood avens, Geum urbanum, has flowered well and its hooked fruits make a modest feature, especially when the sun catches them.


Fungi have been rather few, but there was one fine birch boleteLeccinum scabrum, with its subterranean mycelium no doubt growing symbiotically with the roots of the large birch tree in M3.


While carefully scrutinising the oak sapling in the Penumbra I had no difficulty in discovering this larva of a harlequin ladybird (Harmonia axyridis) sitting as bold as brass on top of a leaf.


Three weeks later there was only a pupal skin in the same place on this leaf and a distinctively patterned adult wandering round at the top of the shoot, an adult which I suspected was the same individual as the larva and the pupal skin.


The harlequin ladybird is a predatory alien invader and the adults are polymorphic with many different forms and colours.  They hibernate in large gatherings in houses and our neighbour had them flying in through his open door and settling on the walls and ceiling.  Standing outside one could see them homing in like honey bees to the hive.

Another alien invader is the ram's horn gall wasp, Andricus aries.  I found two of these galls on the same oak sapling as the ladybird.  It was first recorded in Britain in 1997, since when I have found it in several places locally and suspect it is widespread in southern Britain and the Midlands.  The gall is distinctive by its long single or double 'horn' whose function I do not know.  It does not seem to provide food for the larva(e) within, nor would it be likely to deter predators unless they saw the gall as something unlikely to contain a nice, juicy grub.





Saturday, September 15, 2018

15th birthday of the project

I have now been studying the Square Metre (aka Emthree and the Green Sanctuary) for 15 years.  It has changed almost beyond recognition from a square of short grass to, effectively, secondary woodland.

The picture above is very similar to the one I took on 25 August this year and highlights how slow change is in projects like this.  Worth noting that nearly all the woody plants - hazel, small flowered sweetbriar, birch, holly, sallow, oak, hawthorn, sycamore and hornbeam - have all survived the dry summer.  The one exception is the ash to the left of the birch trunk which has died (of ash dieback disease I suspect).  

Generally though Emthree is less biodiverse than it was in its early years, especially in terms of the flora.  This is perhaps because it is more shady, though I suspect that many of those early plants were pioneer species that somehow managed to find a small square of open ground.

Today, as usual, there were new things to look at and to ponder like the red campion leaf filled with shot holes made, perhaps, by the caterpillar of a Coleophorid moth.


There was a large muscid fly sunning itself on the birch trunk.  A Phaonia species I think and it made me notice how regular the little ridges are on the birch bark.  All roughly the same length, the same height and similar spacing.  What are they for I wondered.  Presumably some bit of birch DNA determines their position and shape.



I was 65 when I started this study and now I am 80.  Roll on the next 15 years to 95!  (Maybe I ought to do some succession planning).


Saturday, August 25, 2018

Dry summer notes


There has been scarcely any rain since the beginning of May and this has affected the more open parts of M3.  The rush plant on the left of the picture has collapsed but many other plants survive.


Today I noticed that the large birch tree was struggling.  The branches are hanging much lower than usual and the leaves look dry and dull.  In the picture below the sallow(top centre) has the bright green leaves and appears to be doing much better than the birch.  I would have expected the reverse to be the case.


In Medlar Wood, the more open habitat has induced the tutsan (Hypericum androsaemum) to flourish with a fine crop of ripe black fruit and an unripe red one.

Various things attack the leaves on the oak cordon in the penumbra.  The picture below shows feeding damage from what I think was a coleophorid moth caterpillar.  The larvae of these make cases and creep around like hermit crabs boring holes in patterns.  I looked for the culprit but it must have gone to ground months ago having left its signature on this leaf.





Saturday, April 21, 2018

April reflections

We are having an April heatwave: plants are growing fast, the ground is drying.  A white butterfly, probably a small white, flew round and over M3 before disappearing into the trees.  Two white flowers are out on herb robert and there are several hairy bittercress plants in bloom (below).


The wood dock at the eastern end of Mice&Red (see below) has enlarged very quickly.  It is as good as a Hosta.



There was a visit from a comma butterfly.  It fluttered carefully between various leaves, seemingly testing them to see if they were nettles and suitable for egg laying and the subsequent sustenance of her caterpillars.

The sorrel plants (Rumex acetosa) have flowering stalks surging upwards.  The tops look like red and green hard roe. Several wasp-like nomad bees (Nomada sp.) were present flying low over the ground among the grasses and herbs, searching no doubt for the nests of mining bees in which to deposit their eggs.  They are cuckoo bees, cleptoparasites with larvae that eat the food that was intended for the larvae of the host.

Today's butterfly was a speckled wood that settled on a red campion leaf.  With its head pointed directly towards me and its wings held over its back, it was remarkably hard to see.

Wednesday, April 18, 2018

A new log seat

With the help of our granddaughter, I stacked a couple of large rounds of wood to make a place where I could sit and contemplate The Square Metre.  The lower log is an old round of sweet chestnut and the upper is from the incense cedar that blew down last year.  It has acquired a bloom of green algae in its top and I vaguely wondered how I might identify this (our native trees do not seem to develop algal blooms like this). Note also the dandelions flowering on Troy Track in front of the logs.  They appear to prefer to grow on trodden ground.


The birch tree in M3 is full of catkins, but you have to look upwards to see them well.



Saturday, April 14, 2018

Flies, ferns and trees

Now spring is advancing rapidly there is a large variety of bees and flies sunning themselves on the trunk of the birch tree.  For example, the hoverfly below.


Over the last few days there have been several male sallow catkins (Salix caprea) on the ground in or near M3.  They must have come from the large example some twenty metres to the south which has flowered well this year and I suppose they must have been blown across, though I do not recall seeing this before.  They may be just fallen flowers but there is enough left in them to support and protect the sallow fly larvae (Egle spp.) that live inside them: a good example of a symbiosis where both species benefit and no harm is done.


In Planet Terracotta a leaf of the wood anemone (Anemone nemorosa) has appeared as it usually does.  It has now survived in this rather hostile environment for ten years, but shows no sign of flowering or spreading.


In contrast to the wood anemone, the broad buckler-fern (Dryopteris dilatata) continues to enlarge and now has seven fronds. They grow very rapidly once they start, but I wonder why they don't all develop at the same rate.  It has an Award of Garden Merit from the Royal Horticultural Society and is a very common wild plant in our area.


Another fast developer is the sycamore (Acer pseudoplatanus).  This year at least six seedlings have appeared, more than at any time before.  As seedlings the species is very attractive but, if left, I fear they would come to dominate the whole of M3.  Considered by most to be an introduction, there are relatively few insects that eat the leaves and, with its fast growth, it can quickly become a dominant or the only species where it flourishes.  As I said when I found a sycamore seed in M3 last autumn, I do not know the source of this species as there are no trees nearby that I know of that are large enough to bear fruit.






Wednesday, March 14, 2018

Bee time

A mild and sunny day and the insects are starting to reappear.  At about midday there were two queens of the tree bumble bee Bombus hypnorum flying about and scrabbling on the ground as though looking for somewhere to nest (though this is normally an aerial nesting species)  It has been expanding rapidly in Britain since its first record in 2002 and is common in our garden.  It is readily identifiable from its brown-haired thorax and white-haired tail.


On a sunny day the trunk of the birch tree in M3 is a magnet for flying insects.  Today I noted many sallow catkin flies (Aegle spp.) and two mining bees: the small sallow (Andrena and Clark's (A. clarkella).  The Aegle spp. (see below) are always common here when the sallows are in flower as the larvae live in the fallen catkins.


The Clark's mining bees have a nesting aggregation on the root plate of a windthrown chestnut just beyond the end of the garden which is probably where this male came from.  Both mining bees are very fond of visiting the catkins of sallow trees and there is a very large example of Salix caprea just coming into flower a few metres south of M3. The picture below is of a male Clark's mining bee: the small sallow bee was too quick for me.


Tuesday, February 27, 2018

Morning snow

The weather has turned bitterly cold with a huge anticyclone (known as the Beast from the East) heading in across mainland Europe from Siberia.

There was an appreciable amount of snow this morning and I ventured out to see what it had done to the Square Metre.  Interestingly, unlike the rest of the garden, it was almost snow free, I think because it lies on the southern side of a hedge and can catch any sunlight that is going.  This gives it an appreciably warmer microclimate that elsewhere in the neighbourhood.  Note that the area beyond the hedge and on its north side has an unbroken snowfield.


It is in weather like this that the self sown holly just to the right of the birch tree comes into its own.




Friday, February 02, 2018

Return of the thrush?

The broken shell below is of a brown-lipped snail, Cepaea nemoralis.  It is resting on the Lyon Stone on the western side of M3 and it looks very much as though it was battered open by a thrush using the stone as an anvil.  In 2004 a thrush was very active in the area using a different piece of stone as an anvil but they do not seem to have been common in recent years.


I have written about the stone elsewhere.  It came from the river Lyon in Glen Lyon, Scotland and was given to me for no obvious reason and without explanation by an acquaintance who had just returned therefrom.  There is all sorts of magic and mystery about these stones and I rather treasure it.  Much about the stones of Glen Lyon here http://philipcoppens.com/glenlyon.html





Tuesday, January 30, 2018

Where did it come from?


I found this old sycamore key today lying like some strange deep sea fish on Troy Track on the eastern side of M3.  Winter had shredded the blade of the samara revealing the sinews that hold it all together with the muscular, batswing fingers stretching from the seed casing.  This casing is slightly chewed as though some creature was, unsuccessfully, after the seed.

There is no fruiting sycamore tree near M3 though two or three seedlings have appeared over the years, so I wondered how far it had samaraed through the air before coming to rest.  Despite careful scrutiny I could find no microfungi on it so I have put it in a small plastic box with damp paper to see if anything will incubate.

Tuesday, January 16, 2018

A first spring development

I look at M3 practically every day now to seen any signs of spring ahead.  There seems to be very little, but in the last week or so these leaves of cuckoopint (Arum maculatum) have emerged by the old yew log in the penumbra area.


The leaves are beautifully fresh and green and, in this example, patterned with purple black spots (hence the specific name maculatum, I suppose).  These spots only occur on some of the plants and I have read that they are caused by a fungus Melanustilospora ari.  

Tuesday, January 02, 2018

Ash bark lichens, changing winds

The start of 2018 has been depressingly grey and wet so I was pleased to find something to attract my attention.  The smooth grey bark of the ash tree has quite a few scarcely visible, circular patches of lichen.  I think the species might be Opegrapha atra though this is very close to O. herbarum and some other species.  Getting an accurate determination will need microscope work I think.


On a rather larger level there have been further changes to the area surrounding M3 inasmuch a large whitebeam that has grown some 20 metres west of the project has blown down.  The reason is, I suspect, that many oaks were removed in the autumn from a garden to the north and this has allowed winds from the north to topple the whitebeam.  With the incense cedar to the south this will make a considerable change to the pattern of wind circulation in and around M3, though I doubt whether I shall be able to disentangle the effects of this from changes brought about by increased light levels and other factors.

Sunday, December 24, 2017

Hornbeam bark stripping


The picture above was taken looking down  at the one metre tall hornbeam cordon that has been with us for ten years.  I prune it back every autumn and some of summer's cut twigs with their dark green bark can be seen.  There are also some white twigs (particularly the one in the centre of the picture) from which the bark has been recently stripped and any leaf buds gone.

I suspect a vole or mouse as the probable culprit as the work is all too small and delicate for a squirrel or deer.  I hope it doesn't continue to the point where it has a major effect on the hornbeam.

The white trunk in the background on the left is the lower part of the M3 birch I talked about in yesterday's post.

Saturday, December 23, 2017

Colours of birch


One of the most conspicuous features of the Square Metre at this quiet time of year is one of the root buttresses of the birch.  This tree appeared as a seedling in spring 2004, nearly 14 years ago.  The orange tan exposed root (I think it is root rather trunk) runs from the craggy base of the tree on the left for a few centimetres before disappearing underground.

I wonder why it is so brightly and differently coloured that the rest of the tree and why it has raised ridges encircling it.  It must be dancing to the beat of a different drummer than the rest of the tree, but is there any reason for it?

The trunk of the tree further from the ground is generally white with black marks but it is washed with the palest pink on the northern side and palest green on the southern, the colour mainly being on the fine strips of outer bark that are constantly peeling off.  Many of the colours in nature seem to have no especial significance and I suppose they are just evolutionary by products conferring no particular competitive advantage.

Not far from the birch I noticed a group of ivory coloured seeds on the wet fallen leaves.  I have seen similar arrangements of seeds in the past and I think they are made by mice.  However, I am not at all sure what these are seeds of.  Maybe one of the irises - gladdon or yellow flag - both of which grow nearby.