Fron Wyllt again

Interesting afternoon walk at Fron Wyllt, taking a quick look at the Beech leaves, Fagus sylvatica, on the trees which appear to be planted near the car-park, on both sides of the river. Toby is definitely gradually getting more used to my no-doubt boring stops to look at leaves!

I found about half a dozen relatively short Phyllonorycter mines which seemed to have a strong central crease. Some of these seemed fairly old and abandoned. This would fit in with Phyllonorycter messaniella, which seems to fold and distort the surface of the leaf quite strongly in most of the pictures shown. I saw one particularly long mine, still apparently with a central crease, but there are photos on the internet showing equally long mines that are identified as P. messaniella. These mines could be up against the midrib, or they could be away from it, mostly half way out towards the margin of the leaf. 

However the other possibility is a highly contracted long tubular mine which is said to have several pleats but these might look like just one, and I found three of these, two side by side on one leaf? So Phyllonorycter maestingella was confirmed, and I will come back to this later.


Phyllonorycter messaniella

Phyllonorycter messaniella (Zeller, 1846), Zeller's Midget, is also known as the Garden Midget - arbitrarily? 

According to UK leafmines, the mines are generally active in March - April, again in July and then October, although these dates seem rather tenuous (?). Perhaps its July to October? They don't really fit in with the idea that the third generation only occurs overwintering on the evergreen Holm Oak, December to March. On Beech and Hornbeam this species is said to be found on the lower surface between two adjacent veins, with a sharp fold.

Another more detailed description from the excellent Bladmineerders website is "oval, lower-surface tentiform mine, 9-14 mm long, mostly between two lateral veins. The lower epidermis with a single sharp fold (sometimes forked near its end). Pupa in very flimsy cocoon, that contains a bit of frass laterally and at the rear end".

Polyphagous on woody plants, not uncommon on Beech. However, the Dutch view is that the main host is Oak, although I haven't looked for it there yet. 

It was accidentally introduced into Australia and New Zealand, where it turns out to be regarded as a pest, mainly (and initially drastically) on introduced oaks, etc, but including on members of the native Southern Beech genus, Nothofagus. Initially it ran riot in New Zealand with an average of many mines per leaf until European parasites were introduced, when some degree of control was developed as would be found "naturally" in Europe. 

Phyllonorycter maestingella

The significantly longer mines on these leaves belong to this species, the monophyletic Beech Midget (Muller, 1764). The several folds may appear as one, and the silk is strongly contracted, often leading to a tubular appearance.

It has two broods, the adults flying late April to June, and again in August. The mines are therefore usually active in July and September to October. The insect then hibernates as a pupa, presumably on the ground.

Agelastica alni, by golly

Walking through the pretty woodland nature reserve of Fron Wyllt, I looked at the leaves of some Alders by a small bridge over the rapidly flowing stream.

On the first day I noticed that they had been a bit frazzled.

On the second day I actually thought about it, and wondered whether they were sawfly/slugworm larvae that might be responsible. It sort of occurred to me (very slowly) that I might not have seen this damage on Alder before. It looked a little like the shredding or skeletonisation of beetle larvae damage (as I have seen regularly on Viburmum in recent years) or slugworm damage (as I have seen in the past on Birch). Eventually I found a larva which I thought I recognised as a slugworm style of sawfly larvae. A nasty-looking glossy black caterpillar.

When I got home I saw references to Alder Sawfly, but that is white and spiky, so it was not that. By chance I came across many US references to an Alder Flea Beetle with very similar larvae and blue adults. But this apparently doesn't occur in Europe. I was now intrigued and I finally came across references and photos relating to Agelastica alni, a beetle thought to be possibly extinct, but rediscovered and apparently spreading across several parts of the UK. Oddly enough, it looks very similar to the Flea Beetle from the US.

Here is a photo of a larva on apparently fresh damage, near the base of the leaf.

And another, with slightly older damage,

Here is a photo of older damage, no larva seen.

And a photo of skeletonised leaves against the sky, indicating what potential damage could be done to the Alders along our streams and rivers.

This is the site where the worst damage was seen,

Ganoderma on Horse Chestnut by the Meanders Bridge, near Hope Farm

 A nice cross-section of the conk, hopefully the right way up:

The tree is not looking at all well, with badly cracking bark:

Alder leafmines

Phyllonorycter klemannella, (Fabricius, 1781), the Dark Alder Midget 

The first and possibly much the commonest mine I found today was Phyllonorycter klemanella (=kleemannella), the Dark Alder Midget. I was only looking on a few lower branches of an alder on the north side of the Bourne opposite Easterfield Bungalow.

These mines were both away from the midrib, and also close to the midrib. They showed no strong creases (so the mines were not Phyllonorycter rajella, larvae June and July), and it is the right time for the second generation of these larvae in the year, July- August. The mines were not long and thin enough to be confused with Phyllonorycter froelichiella, which is also un-creased, but with grey larvae, usually a bit later in the year, such as September-October. All these are underside mines on Common Alder, as opposed to Phyllonorycter stettinensis, which is strongly creased, characteristically yellow-green and on the topside of the leaf over a vein, larvae May and July-August but can be as late as November.

There were active green fresh mines but there were also other older mines, some emptied, which might have been from the first generation, May-June, or already-hatched mines from the second generation. Here is a supposedly typical fresh oval mine of Phyllonorycter klemanella (=kleemannella). 

Here is another mine, from the upper side of the leaf.

Phyllonorycter stettinensis (Nicelli, 1852), the Small Alder Midget

I did also find two, or a few more, examples of Phyllonorycter stettinensis, on the upper side of the leaf. This is yellow green, with one strong central crease, the timing is right for the second generation  but in this photograph it is NOT over a lateral vein, as described in Bladmineerders. A second mine was over a lateral vein, so that is OK!

This mine is apparently much more typical, over the vein,

Phyllonorycter froelichiella (Zeller, 1839), the Broad-barred Midget

I may have found one or two examples of this leaf-miner, but it is a bit early for this particular species. Also this particular mine does look as though there is the start of a single crease in the mine, which would be unexpected in froelichiella, so maybe this is a misidentification. With this crease it could be rajella.

I need to check back, but I don't seem to have ever seen froelichiella for sure - I will check through as much as I can.

.Phyllonorycter rajella (Linnaeus, 17589), the Common Alder Midget

Why haven't I found this species on the leaves of this tree? The larvae should be found in June/July and more in September/October, and I would have expected to find it by now.

Heterarthus vagans ( ), 

This is a possible, but not definite, identification,

Dasineura ulmaria, a Leaf Gall midge on Meadowsweet

 

Possible ID. Found somewhere along the River Bourne walk on a Meadowsweet plant.

Butterflies at Leybourne

Nice walk through the recently created meadows today with the trainee group of butterfly surveyors, and saw one or two Small Coppers, Common Blues, Small Whites, Large Whites, four Painted Ladies and lots of Gatekeepers and Meadow Browns. A possible Red Admiral was seen.

A couple of Speckled Woods over on the path around the Ocean, nice to see.

Iteomyia capreae, a willow leaf gall initiated by a gall midge larva.

 

Found somewhere along by the River Bourne. 

BBQ near Harrietsham

Red Admiral on the lawn, and a nice collection of perhaps rather crowded trees. One of the purple plums had a couple of Ganoderma applanatum brackets on a dead stump. I rubbed the edge of the spore surface and it turned brown immediately - the spores?

Sweet Cicely I thought at the bottom of the garden, in the hedge by the side road.

Ganoderma australe/adspersum possibly

 

This perennial bracket is a common feature of the basal area of many broad-leaved trees in the UK. Perhaps G. adspersum is the better name for the examples found in the UK? 

I THINK this is a fairly typical shot. This species is separated morphologically from the closely related Ganoderma applanatum by its thicker cuticle or upper surface, consistently over 1 mm thick. Ganoderma australe/adspersum is by far the commoner, and thought to be most aggressively parasitic. Ganoderma applanatum is more generally confined in its saprophytic role to already dead and moribund trees. 

Where targets are at risk and the conks are noticed, then the hollowness and the stability of the tree where the fruiting bodies have been seen should be checked. This particular photograph was actually taken at the start of the month two years ago, near Harrietsham while we were attending a BBQ. I cannot remember whether we checked the surroundings very carefully, but my memory tells me that this might have been close to a relatively quiet country road.

As a result of its thinner cuticle, the upper surface of G. applanatum is often softer and depressable with a thumb or finger, whilst G. australe/adspersum is much harder and has no give. "This should be tried on fruitbodies appearing to be at least two years old and upward but not applied to old fruitbodies with crumbling cuticles." What do we make of this?

This age threshold should also be applied when observing and comparing the "context" of the two species, i.e. the thickness of flesh layer between each season’s tube growth. Here the thickness difference is the other way round, it is thinner to non-existent in G. australe/adspersum!  http://www.londonfungusgroup.org.uk/wp-content/uploads/2016/09/Ganoderma.pdf

In Ganoderma applanatum, the margin of the conk may also often be thinner/sharper, and there may be its characteristic fly galls on the lower surface, which are never found on G. australe/adspersum. If you were to find a Ganoderma on a conifer, there are no to very few records of G. australe/adspersum on conifers in the UK, whereas there are some of Ganoderma applanatum, but there are other species to consider!

Perforate and other St Johns Worts.

Well, always a bit of a tricky genus. One of the things I should always do is to check that the plant isn't hairy at a fairly early stage, and whether the flowers are a rich golden yellow or a paler more acid level of yellow.

At least partly in retrospect, these flowers in Dene Park are a golden yellow, and the petals are longer  than the sepals.

In this case I did remember having looked at the leaves to see that they were perforate, to check to see if there were any black dots around the edge of the underside of the leaves and petals - there were. This isn't unfortunately a character! The stem felt round with two small but clear ridges. In theory this species can be up to 80 cm tall, but is often less.

My next step was a bit more solid, to check the sepals which were actually pointed (rather than blunt), but without any obvious stalked black spots (although there could be some according to Stace, generally un-stalked). This is now beginning to look like perforate St Johns Wort, Hypericum perforatum.

There were no black streaks or splashes on the petals, the stems were not squared off, there were "perforations" in the leaves, and the soil wasn't notably damp, the sepals weren't spotted (often in lines) and unequal (?), so it doesn't look like imperforate, Hypericum maculatum ssp obtusiusculum, which I think I might have seen down towards East Lock perhaps - but its actually very rare in Kent.

The plant did not have a stem that was reddish with four wings, and the flower was not notably pale, with the petals only a little longer than the sepals, very few perforations, so it was unlikely to be the Square-stemmed, sepals also not very stalked-dotted, Hypericum tetrapterum.

The plant didn't look a bit like tetrapterum slightly four edged, but with sometimes red-flushed bright yellow flowers, wavy leaves with plenty of perforations and black dots on its pointed equal sepals and possibly elsewhere, quite rare in marshy places, Wavy St Johns Wort, Hypericum undulatum. Not in Kent.

The plant wasn't erect but downy, with roundish stem, longer and more strongly veined leaves with perforations, paler yellow flowers and fairly obvious stalked black dots on the sepal (and possibly also sometimes petal) edges, so shouldn't be the Hairy St Johns Wort, Hypericum hirsutum. Mainly on chalk.

The plant wasn't downy except on the upper surface of the leaves, with longer strongly veined leaves, but without perforations, although similar paler yellow flowers and obvious stalked black dots on the sepal edges, so shouldn't be the Pale St Johns Wort on calcareous soil, Hypericum montanum. Only West Kingsdown and Darenth.

The plant wasn't in an acidic bog or marsh in the west of the country, with procumbent stems rooting at its nodes, grey woolly-hairy almost circular leaves, and with sepals with reddish dots on the edges, so it wasn't Hypericum elodes. Only Hothfield and Bedgebury.

There is the very erect slender-stemmed species with blunt oval leaves with cordate bases and perforations, petals orange-yellow, with reddish undersides, with black stalked dots on the edges of the petals and the sepals, Hypericum pulchrum. Woodland rides and sandy heaths. Hopefully seen on the grassy area at Dene Park.

Equally the plant wasn't creeping across the ground, smaller oval leaves, with smaller pale flowers, petals a bit (but not twice) longer than sepals, "normally" dotted sepals and a round but two-ridged stem, so it wasn't Hypericum humifusum. I think I have seen this on the sandy soil at Pembury.

There is the rare toad-flaxed leaved species, Hypericum linariifolium, upright, round un-ridged stem, longer, more linear leaves with very few perforations, petals more than twice length of sepals, lots of stalked black spots on sepals, Southwest and Wales on acid rocks, so obviously not in Kent.

That looks like all the reasonably likely herbaceous Hypericums!