A busy day with parish matters first thing, everything from village home security, youth club, goalposts and dog orders to clearing rose briars from footpaths, followed by house painting, college prep and shopping before it was time to walk Monty. We are off to Scotland tomorrow, so a list of things to do tonight as well!
I travelled a bit further today, to the North and over the Lower Greensand Ridge to the start of the dip slope on the far side, where there is a very large iron age fort, Oldbury Hill.
The site is covered by acid woodland, with sessile oak, beech in the canopy (no ash!), mountain ash, holly and hazel (no hornbeam!) in the understory, and a limited amount of bilberry with only a little bramble and bracken in the field layer. The soil is sandy and infertile as well as acidic.
The light was very poor right from the start today but was really going by the end of the visit!
This is the bilberry, Vaccinium myrtillus which is quite a rare plant in Kent, where acid soils are uncommon
The beech leaves were checked out for the usual mites and insects and sure enough the following were reasonably widespread through the foliage: Eriophyid mites causing the upper leaf roll on the leaf margin, and the erineum on the lower epidermis respectively, the gall midge Hartigiola annulipes causing the pocket gall on the top epidermis along the veins, the leafmines caused by Phyllonoricter maestingella and lots of leafhopper damage on the leaves. Again the only species missing was the Eriophyid mite that causes the lines of felt directly over the veins - the only time I've seen this year was just on one leaf at Bitchett Hill, and I didn't photograph it!
However there was at least one new appearance, that I had been hoping to see at all the sites I've been looking at Beech so far, Bitchett Hill, Dene Park and Clearhedges and had had no definite luck with to date. This was the serpentine mines caused I think by Stigmella hemargyrella. There are two Stigmella species on beech and both cause serpentine mines, but with the other the egg is laid, and the mine therefore starts, right next to the midrib, so we know its not that.
This is a better photo and the frass shows up darker and more neatly in the middle section of the mine, as described in the books and web reference material, but still not clearly "coiled".
This extra addition does probably indicate that beech has been growing there a long time and the fauna is therefore nearer a complete list. But still no sign of the mines Phyllonoricter messaniella, Stigmella tityrella (but wait for the 30th October, up in North Wales), Parornix fagivora, the weevil Orchestes fagi (but wait for the trip to Tomich) or the gall formers Mikiola fagi, etc., so still quite a lot to look for!
This doesn't look quite like a leaf-mine to me - although very similar patterns of dead tissue can be found quite commonly on beech leaves. There always seems to be one "entry hole" per patch and I would guess that these patterns are caused by fungal infection following an attack on the leaf, for example by the Hartigliola gall midge, whether or not the midge gall develops or not. It just has that sort of "jizz" about it:
Something new seen just visiting the leaves was this scorpion fly - I saw a similar insect in the hedgerows by West Peckham a few weeks ago,
and here is an unknown Tachinid, perhaps its very heavily "dusted" to give it this grey appearance,
This is the very common, and indeed the only, leafmine on holly, Ilex aquifolium, caused by a fly Phytomyza ilicis,
Its still a little early for many fungi, but here is a smallish bracket fungus, an annual saprobic or necrotrophic fungus usually on dead or weakened trees of the weeping birch, Betula pendula. This is the Birch Polypore or Razor Strop Fungus, Piptoporus betulinus, bits of which were famously found in the sack of the "ice-mummy" frozen into an alpine glacier 5,000 years ago, Otzi the Ice-Man! He could have used it to put a fine edge on a knife, or for starting fires, or for medicine, or for more than one of these purposes, no one really knows.
View of the upper surface first.
Then the lower, with its characteristic "rolled" margin. The mycelium causes a yellowish to brownish cubical rot that sometimes smells strongly of green apples.
This is a very large growth on the butt of an oak tree, cause unknown although it could perhaps be the Crown Gall bacterium, Agrobacterium tumefaciens.
Unknown species of moss on stump, perhaps something along the lines of Thuidum tamariscifolium.
And finally a moss of the tougher variety, Polytrichum species, common in woodlands and quite tough/resistant to drying conditions.
I travelled a bit further today, to the North and over the Lower Greensand Ridge to the start of the dip slope on the far side, where there is a very large iron age fort, Oldbury Hill.
The site is covered by acid woodland, with sessile oak, beech in the canopy (no ash!), mountain ash, holly and hazel (no hornbeam!) in the understory, and a limited amount of bilberry with only a little bramble and bracken in the field layer. The soil is sandy and infertile as well as acidic.
However there was at least one new appearance, that I had been hoping to see at all the sites I've been looking at Beech so far, Bitchett Hill, Dene Park and Clearhedges and had had no definite luck with to date. This was the serpentine mines caused I think by Stigmella hemargyrella. There are two Stigmella species on beech and both cause serpentine mines, but with the other the egg is laid, and the mine therefore starts, right next to the midrib, so we know its not that.
This doesn't look quite like a leaf-mine to me - although very similar patterns of dead tissue can be found quite commonly on beech leaves. There always seems to be one "entry hole" per patch and I would guess that these patterns are caused by fungal infection following an attack on the leaf, for example by the Hartigliola gall midge, whether or not the midge gall develops or not. It just has that sort of "jizz" about it:
View of the upper surface first.
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