Ferns with Ros Bennet

We had a lovely day with Ros Bennet and the Kent Wildlife Trust today, learning to identify ferns in the Kent countryside.

Our first field visit was to Quarry Wood on the Lower Greensand scarp above Yalding, where we found a huge Wild Cherry, which was already on the Kent Heritage Trees database and map.  There were two very large fructifications of Chicken-of-the-Woods, one at the foot of the tree and one much higher up. These fructifications are quite whitish and might actually have been active last autumn. The tree is one of the largest Wild Cherries, Prunus avium, I have ever seen.

Chicken-of-the Woods or Sulphur Polypore, Laetiporus sulphureus, may well be a  group of species rather than just one, according to US research. It is regarded as a saprophyte rather than a major parasite, and may be just one in a longer line of problem that this massive tree has experienced over the years. It was recorded by the Kent Heritage Trees Project 6 years ago, and a split trunk, brown cubical rot and 4 holes were listed then, as seen now. It was recorded as tree 599 recorded by Stephen Foster at TQ7170351838.

More information on some arboricultural fungi such as Chicken-of-the-Woods, https://arboriculture.wordpress.com/category/fungi-2/laetiporus-sulphureus/

This is the tree is its woodland context;

There is a good range of trees on this woodland site, including some very large Ash. This is an old Ash Pollard stool, definitely worthy of note. I do not know why this one was originally selected for pollarding:

We passed one of the specialities of this reserve, Paris quadrifolia,

There were also a few fungi to be found, such as these Ganoderma brackets:

and this "candlesnuff" relative on fallen deadwood, each about an inch or so high, possibly Xylaria longipes:

In one part of the wood we found one "clump" of Hard Fern, Blechnum spicant. The speciality of this species is the split between the vegetative fronds on the outside and the fertile fronds (with obviously narrower "linear" pinnae) in the centre of the clump. Most Blechnum grow from a rhizome, but this particular species grows in a neat tuft. Each of the fertile pinnae in the centre (one is visible here) bear two rows of sori. This species is often sold as an ornamental.

The next fern we were shown was the Male Fern, a fairly simple bi-pinnate structure, with neat rounded-oblong. There are sparse pale scales on the stipe and rachis. This is the (fairly large) shuttlecock, with many vigorous fronds.

Here is a closer shot:

Close by was a shuttlecock of a Lady Fern, Athyrium filix-femina, near an Ash tree trunk, which immediately looks "frillier", possibly tri-pinnate. The species is found across the Northern hemisphere.

I think this is a Lady Fern frond unfolding:

Also quite frilly is the quite robust Broad Buckler Fern, Dryopteris dilatata, with its mitten and thumb pinnulet structure. The stipe and rachis are well covered in golden scales. The sori are covered by a kidney-shaped indusium, as with other Dryopteris species.

Having explored Quarry Wood thoroughly, we moved on.

There are also a number of "smaller" ferns in Kent, quite a few of which may be found growing on walls. This is the Black Spleenwort, Asplenium adiantum-nigrum, growing on a northerly wall of Marden Church. While a little difficult to identify from a distance initially, there is a tidy and relatively glossily green medium-sized triangular frond, and characteristically the stipe is a clean almost glossy black. In fact there are two species of fern here, the Black Spleenwort in the centre, and what might be a Shield Fern surrounding it.

The Spleenwort reveals itself when looked at closely - the pinnae are beautifully set and very similar to the pinnae of the Wall Rue, a much commoner species of Asplenium. It is a bit difficult to describe, but it's the rounded roughly "diamond" shapes of the individual lobes that are characteristic. Overall the frond is roughly bi-pinnate and this speciesn is quite flat or 2-dimensional. That is however quite distinct from the Wall-Rue, when the pinnae are HELD in a specifically 3-dimensional manner.

The green can be quite yellowish - perhaps because of lack of nutrition growing on the wall, as it is normally described as dark green (?).

From the angle above the dark stipe below the green rachis is of course invisible, but was very obvious when the fronds were moved, or from the top, as below.

The form of the fronds can be quite variable - it often seems thinner, with more space in between the branches, and the tip may be more pinnate than bi-pinnate. The other spleenworts (maidenhair and green) are all singly pinnate, and very clearly so.

At Linton Church we found Western Polypody on the wall by the road, although I do not think I will ever be able to tell one Polypody from another. The single fronds emerge singly from a rhizome.

While visiting Linton to look for ferns on the church wall, we had a look down the Lower Greensand scarp across Linton Deer Park on the slope, with its Fallow Deer:

Riverhill Himalayan Gardens

The two specimen of the Chinese White Limes or Oliver's Limes, Tilia oliveri Szysz., on the east end of the front terrace are looking a bit tatty really, although on the plus side, the Mistletoe plants do love them - perhaps a Mistle-Thrush or two might be involved.

From above, the sub-cordate leaves looked a rather acidic lemony yellow rather than a dark green, while from below a very uniform whitish or light grey colour is produced presumably by the tomentum (stellate-downy). The base of the leaves is quite unequal, looking as though the leaf is set upon the petiole at an angle. Things I did notice were the (glabrous) smooth glossiness of the young shoots, and the quite long petioles. I didn't notice the colour of the bark.

The plants originate from moist forest in NW. Hupeh, in Central China, ranging from 1,000 to 2,000 metres altitude.

Hilliers describe it as: "Medium Tree. This is an elegant domed -shaped tree, leaves dark green above and silver-white beneath. Very pretty in wind. It has silver-grey bark which is clear and smooth. This tree is clear of aphids.". There is also an excellent article in "Trees and Shrubs Online".

It is listed as fairly narcotic to bees.

Westgate Park

There is this lovely Mongolian Lime on the city side of the river in among the collection of other ornamental trees.

It is said to be a relatively small lime with great autumn colour according to the books, with several cultivars available in the trade. It grows quite slowly at first, however the TROBI champion in Yorkshire is about 20 m high, twice the height mentioned in many catalogues (not Burncoose). The smaller branches are quite densely packed and the overall shape of the tree is rounded or oval. The mature leaves resemble (to me) birches from their shape, colour and texture all together, while the young leaves emerge bronze, reportedly quite attractive. It flowers quite early, and is said to be bee-attractive. However it may not be attractive to aphids, and may be honeydew free.

The yellow autumn colour is really good, and has therefore been used in the hybrid with the small-leaved lime, 'Autumn Harvest'.

It was discovered by Pere David in 1864 and brought to Europe in the late 19th century, seed being sent to Paris in 1880,  and the Arnold Arboretum in 1882 and is now grown in quite a few situations. Its native habitat is in Mongolia, Eastern Russia and Northern China, at about 1,000 m, the altitude of Snowdon. It is an extremely cold-hardy tree, tolerating minus 20 C.

Alders at Leybourne

I found what appears to be a third Grey Alder at Leybourne Lakes today, planted to the south side of the Round Pond.

The bark was a lovely shade of grey, although confused with various lichens.

Botanising in Blean Village

This is a sort of revision for the practical walk we did earlier in the evening.

For example we looked a a couple of sedges. The first was the fairly common Hairy Sedge, Carex hirta, and the second was Grey Sedge, Carex divulsa,

Hairy Sedge, Carex hirta, has long sparse hairs on the edges

The Grey Sedge, Carex divulsa, was found in a hedge bottom along the pavement, on the way back close to the village hall. This has long narrow droopy dark green leaves in loose (dense, surely??) tussocks of many stems. The inflorescence is spaced out small clumps of nutlets, with a thin needle-like bract, which is shorter than the inflorescence as a whole.

Lichen on the Blean

It seemed to be quite a coincidence that I stopped to take a photo of a fairly obvious lichen that proved to be one of the key species noted in the area, Thelotrema lepadinum. There are about 20 official records in TR on the NBN database, all in The Blean or down towards Mersham.

It has an unusual appearance as the apothecial bounday membrane is separated from the thallus wall, and appears as a papery membrane inside the throat of the volcano-like apothecia. It is regarded in East Kent as an indicator of an ancient woodland site - possibly. There are no records from West Kent at present. It is much commoner in the north and west of the UK.

The above photo was taken from quite a large well-established patch.

Here is a newer patch appearing on a fairly smooth-barked tree:

Lichens on trees at Yalding Fen

Had a lovely day with the Ash Project and Ishpi Blatchley looking at lichens on trees, particularly Ash Trees, wood and other substrates.

This is one of the common bark lichens we found, Parmelia sulcata, with its exuberant soralia developed from pseudocyphellae obviously in the centre of the thallus, its lovely grey lobes, brown to black on the undersurface.

This I think is a Physcia species, with the narrow lobes, in this case growing on wood, the hand-rail of a footbridge between the central pond and the marsh with the duckboard path. I think it is quite likely to be Physcia tenella, but I couldn't see any developed apothecia, or indeed any of the tiny black spots or pycnidia that you often see in pictures. The cilia on the edges of the lobes are quite visible, so it could perhaps be P. adscencens or P. tenella.

In the more established part of the lichen, the soredia make it look much more fuzzy.

This is an interesting photo of another section of the bridge timbers, with a grey foliose lichen with pseudocyphellae on the lobe to the bottom left of the photo. There are also some tiny black pimples on a surface in front, on the other section of timber.

Here are three different lichens on the top surface of the main bridge timber rail:

Evernia prunastri on an oak or willow perhaps

Usnea?

Grey lichen with black jam tart apothecia, perhaps Lecidella elaeochroma (Ach.) M.Choisy, slightly overgrown by a Physcia species, and with some limited black margins to be seen.

This is the white paint lichen, Phlyctis argena, on one of the trees along the driveway into Great Comp garden. In this instance I couldn't see see soredia (the usual description is soredia abundant or rare) or any apothecia (usual description is rare, but if found they should be dark grey, pruinose, with large muriform spores).