Today I started off with organising painting the exterior of the house and some Parish office work. I got free at about two p.m. so finally got Monty out of the house for his walk, although too late for the best of the weather. Following up on the Beech story from yesterday, there are several compartments of Beech planted up at Dene Park that must be about 40 - 50 years old (actually the stock map shows that these were planted in 1953, so the trees are 58 years "old" from planting as maidens), so I was able to compare these with the mixed age woodland at Bitchett Common I looked at yesterday.
Looking at the ID features first, the trees in both locations are pretty much the same. One of the things to note about the Beech leaves in both locations are the silky hairs along the veins and particularly in the vein axils on the underside of the leaves:
On the other hand, there was one difference, the trees along the track at Dene Park in compartment two (known to the Forestry Commission 5302c) do seem to have much more beech mast than the trees at Bitchett Common, and this is ripening up fast:
The invertebrate population looked quite similar on both sites, with the lepidopteran Phyllonorycter maestingella leaf mines and the gall midge Hartigiola annulipes galls quite easy to find, as yesterday.
The nearer leafmine is the classic Phyllonorycter, but the one behind could either be an old "released" Phyllonorycter, or perhaps another leaf mining insect altogether. Today I found the Phyllonorycter pupae, so I am hoping to rear some adult micro-moths out of them at home!
The other species that was very common today was the upper leaf rolling gall mite (Eriophyid mite) Aceria (Acelitus?) stenaspis, which is not easy to notice unless you know what you are looking for and are specifically searching from it. However once you get your eye in, its quite easy to see. The edge is narrowly rolled and may be crimped or thickened, and is usually a different green or yellow colour in comparison to the rest of the leaf surface. I didn't see any yesterday but I wasn't looking for it so it may well have been as widespread at Bitchett as it was today at Dene Park.
In addition I was able to find patches of an erineum (felting) on the underside of some leaves caused by another Eriophyid mite, in this case said to be Aceria fagineum. This may very well have been on the underside of the leaves at Bitchett Common as well, but I didn't really look at the leaf undersides yesterday. Distribution today was quite patchy, but there was definitely a concentration on one tree in compartment one, known to the Forestry Commission as "5306b".
Of course it is also important to be aware of galls that are not found, and there are still several serpentine mines, lepidopteran or dipteran, a leaf-eating weevil and the gall midge Mikiola fagi that I have yet to discover on beech leaves. This last is quite beautiful, but I have never seen it.
This folding over of whole leaf sections is not really a gall but a Tortricoid caterpillar that creates this shelter for itself, from which it can feed on the leaf (the holes close-by). How on earth does this tiny caterpillar manage this?
So yet another fascinating walk today, even if only on the relatively small canvas of the inhabitants of Beech leaves!
Looking at the ID features first, the trees in both locations are pretty much the same. One of the things to note about the Beech leaves in both locations are the silky hairs along the veins and particularly in the vein axils on the underside of the leaves:
The nearer leafmine is the classic Phyllonorycter, but the one behind could either be an old "released" Phyllonorycter, or perhaps another leaf mining insect altogether. Today I found the Phyllonorycter pupae, so I am hoping to rear some adult micro-moths out of them at home!
The other species that was very common today was the upper leaf rolling gall mite (Eriophyid mite) Aceria (Acelitus?) stenaspis, which is not easy to notice unless you know what you are looking for and are specifically searching from it. However once you get your eye in, its quite easy to see. The edge is narrowly rolled and may be crimped or thickened, and is usually a different green or yellow colour in comparison to the rest of the leaf surface. I didn't see any yesterday but I wasn't looking for it so it may well have been as widespread at Bitchett as it was today at Dene Park.
This folding over of whole leaf sections is not really a gall but a Tortricoid caterpillar that creates this shelter for itself, from which it can feed on the leaf (the holes close-by). How on earth does this tiny caterpillar manage this?
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