Leybourne Lakes

The species aggregate (probably) willow rosette gall, Rhabdophaga rosaria on Crack Willow behind the dipping pond. Hoping to cut it open to reveal the larva!

Salix viminalis hybrid?

Went back to the probable Salix viminalis (L.) x ? hybrid by the gate along by the newly planted birch) today and took a photo of some retrieved leaves. These may not be entirely characteristic as the tree has been pollarded in the recent past, so the shoots are perhaps a bit sucker-like.

My best guess is that it is a hybrid with Salix caprea (L.), known as Salix x sericans Tausch ex A. Kerner or Salix x laurina in the older version of the Kent flora. However it could be the hybrid with S. cinerea

This is a cklose up of the leaves, two upper sides and one lower (the topmost leaf). There appears to be fairly strong reticulate venation patterns (this is what seems to me to be giving a "Goat Willow" look to the upperside of the leaf, and what we hope is a fairly tomentellous underside.

Here is a slightly enlarged view, again showing the "Goat-Willow" appearance of the leaf. The insect damage could perhaps be early Capsid Bug.

Other clues are a largely yellow-green sometimes glossy (lustrous) twig, a slightly recurved, somewhat undulate margin to the leaf, no obvious striae. I could see no stipules at all - possibly they are not noticeable at this time of year?  I am not sure how much before the leaves that the catkins appeared, I need to double-check next year. , The female catkins are of close to 5 cm in length, and are quite numerous clustered towards the ends of the twigs

Salix viminalis catkins

Returning to Leybourne I looked in particular at the catkins of the Salix viminalis plants on the south side of The Ocean. The first plants were female, and the next ones were male.

The female plant was a beauty and at least some of the catkins were still "active" despite it being nearly the end of April. This is a shot of quite near the tip of a twig, with the bud scale still closed over the female catkin, and an Andrena bee, most likely a fairly well worn male, on the right of the twig. The scale of the opening catkin to the bottom left is below, just visible!

This is a shot of a later, but still early, female catkin on the lower right hand side, showing the silky white hairs, with the female stigmas and styles starting to project out and expand into their active Y-shapes. The catkin on the left hand side of the twig, slightly out of focus, has the stigmas more fully expanded. The two catkins (immediately above and above and to the right) are just losing their scales. The twig on the left shows the pruinescence of the young twigs of S. viminalis, making them look dark grey-green before they turn shiny yellow or yellowy-green lower down the twigs.  

Here the same bee is exploring an open female catkin a little lower down the twig, perhaps getting nectar from some of the nectaries in the female catkin.

One of the odd things is the sequence of catkins opening on the twig - here you can see fully open female catkins lower down, and partly open catkins higher up, with closed catkins in between.

Salix city at catkin time

Back to Leybourne Lakes and there are plenty of willows in flower.

The Salix viminalis was fairly well over, but I did find some female catkins that were only just past their best, with styles still in place, and some male catkins still with stames emerging from the inflorescence. This timing fits with Meikle stating that this is one of the first willows to flower, from late February onwards. I don't think that it was that early this year, but I certainly was seeing the tail end of the flowers by now. The female fruits on some trees were swelling with the vestigial remnants of the styles and stigmas only just still visible. It would be interesting to go back around the site checking to see which plants are male and which are female. They would have either been planted or perhaps germinated from seed. The distribution appears to be around "The Ocean" and I would feel this is consistent with planting whips or other propagules when the site was replanted after its use as gravel pits was discontinued. I need to look elsewhere and compare this with its natural distribution along river banks in Russia as according to Meikle.

As in Meikle, the male flowers each have two glabrous stamens, up to 1 cm. long, much longer than the catkin scale. From the same source, the anthers are oblong, yellow, about 0.5 mm long and 0.2 mm wide, and all these points fit with the plants at Leybourne which I have checked.

Murky Leybourne

When I arrived at 3 p.m., there didn't seem to be much light this afternoon, and initially very few birds on the Ocean. However after we got a bit further along the path and I let Monty off the lead, things went OK, with more Tufted Duck on the main water, and interesting ideas coming to mind on the trees by the side of the path. There were one or two Wrens by the wooden swan, and later on, a party of mainly Long-tailed Tits, but with at least one Blue Tit, in the Willows on the other side of the path to the hedge-line Alders in front of the first houses.

Many of the Crack Willows, Salix x fragilis, look very orange on the young twigs, particularly the upswept ones on the lower branches nearer the ground, and these may be a form known as nothovar basfordiana basfordiana, colouring up well as the winter proceeds. These are most obvious on the South side of the Ocean Lake, and the East side of the Railway Lake.

The unknown shrubby willow by the last Leybourne Way entrance could in theory be a White Willow. There are no cracks exposing orange in the bark of its main stem indicating that it might be the Almond-leaved Willow, Salix triandra, that I hope for, but it still doesn't look quite right for a White Willow and there is little to no pubescence on the leaves and twigs, although it is admittedly late in the season. It has retained a thin but widespread covering of small lanceolate leaves, but no overall structural jizz of a White Willow. It also feels as though it is naturally comfortable as a shrub, not stretching up to a tree shape!

On the taller and more likely White Willows there are still a few leaves on many of the brushy twigs. On one or two trees there are numbers of willow catkin galls, caused by a virus or mycoplasma.

Along by the wet woodland area, the Grey Willow Carr, I did find one bush of a yellow-green barked cultivar of White Willow, identifiable as such from its leaves on regrowth shoots. It was also possible to identify many of the Grey Willows from a distance, picked out by their retention of their relatively small obovate leaves, obviously colouring up well and often a good butter yellow.

There was also a "Grey Willow type" shrub there, with much larger leaves, so possibly a Grey x Greater hybrid. On the Italian Alders there was quite a lot of leaf weevil type damage, together with
some possible Heliozela resplendella (Stainton, 1851) leaf miners, indicated by the oval cut-outs seen. The leaves are holding fairly well although a bit dulled and some yellowing as they age.

On the Roaden Island Lake there were several Black-headed and one Common Gull, Larus canus, two Canada Geese and one very close-up Greylag, quite a few Coots, a pair of Mallard and some Tufted Ducks.

On Railway Lake there were dozens of Tufted Duck and at least two male Gadwall.

Hartlake Bridge

I think it is now down to a tree by tree approach as far as identifying Willows goes! I will have to go back to individual trees time and time again over the year to check the seasonal features.

Here is a close-up of the bud on a yellow-shooted form of Crack Willow, tentatively identified as Salix x fragilis nothovar Basfordiana f. Basfordiana (scaling ex Salter) Stace also known as the Basford Willow, first discovered before 1870 in the nursery of Mr. William Scaling. The ID depends the assumption that this is the only yellow-shooted form of the Hybrid Crack Willow, produced it is thought by the original cross of the Hybrid Crack Willow, Salix x fragilis, with the highly colourede vitellina form of the White Willow, Salix alba, but of course this could prove false! However, it seems to be as close as most people will get, unless they are absolute experts, so it will have to do for me.

it is interesting to see the lenticels, the stipule scars, and the hairs on the stem close to the bud - protected from wind and abrasion?

More on Salix city

I walked around the Ocean, anticlockwise, more slowly than the other day, and keeping an eye on as many trees as possible between the path and the lake.

Crack Willows

The first thing I thought was that at the southern end of the Ocean there is a lot of the Crack Willow, Salix fragilis (L.), the majority of the trees on the skyline. Mixed in were Ash, Grey Willow, Alders, Hawthorn, Blackthorn. The upperside of the Crack Willow leaves at this time of year are mid-green and quite glossy, with a whitish grey on the underside. The tip is quite acuminate, while the serrations on the margin are quite prominent, and somewhat uneven. The petiole is generally over 1 cm long, the twigs glossy but of variable colour, or there may be several different types present.

Crack Willow is a complex species aggregate, both in the UK and on the continent. There are many clonal variants, generally unisexual, and most of them are likely to have originated in the catchments and other areas from human activity of one sort or another. The taxonomy is very difficult. The leaves do seem to be a bit more subject to Willow Anthracnose, in comparison to the White Willow, Rusty Willow and Osiers covered below.

I was puzzled not to see obvious glands, usually figured projecting in odd shapes from the junction of the petiole and lamina.

White Willow

Salix alba appears generally to have smaller, neater, leaves obviously glistening white as they billow in the breeze. Close up it may be difficult to see the tiny hairs, except on the edges in profile, in with the minute serrations. The stems are initially silkily pubescent as well, going yellowish as they age. No stipules visible in September, and I didn't see any glands on the petiole.

Osiers

To the south and southeast, and again to the north there are good individual plants and patches of the Common Osier, Salix viminalis, L. One plant had very narrow smaller leaves, and could perhaps have been var. angustissima, but Meikle states that almost any plant will degenerate into this state if sufficiently neglected.

The shoots are generally upright, on what to me seem quite rounded bushes. The short indumentum covering the underside of the leaves and the stems and next year's buds is very attractive. On the stems the indumentum extends about half way down the current year's growth, making the younger stem a lovely silky dull green, but as it wears away, leaving a glossy green epidermis on the older stem. Last year's growth has an matt olive-brown bark covering it. The upperside of the leaves is a dull green, hardly lustrous at all. The revolute margins and the undulations are quite obvious. The underside of the leaves are silky grey with the thousands of tiny apressed hairs, and lots of small veins curving strongly towards the tip, which project downwards below the lamina, so leaving a tiny dip on the upperside of the leaves, and repeating the pattern along the incredibly long laminas. The leaves are often tattered and damaged, perhaps by leaf beetles and/or leafhoppers.

There are, but quite difficult to spot, very long, lanceolate, almost linear stipules. The canaliculate (not very obvious in September) petioles have large boat-shaped bases covering a large proportion of the bluntish woolly catkin-buds laid down for the following year, giving the string of pearls effect noted in the Collins guide. The indumentum of the stem is pierced by orange-brown stomata, generally with a central split. 

Leybourne and Salix city

Its all very difficult when you want to start to get to grips with the genus Salix. At Leybourne there is plenty of scope and there may be Salix alba, Salix fragilis, Salix caprea or Salix x reichardtii, Salix cinerea, and Salix viminalis, together with a large number of variants, cultivars and hybrids. I have suddenly remembered that there is a reference collection of Salix at the Sevenoaks Wildlife Reserve!

This is a suspected Salix cinerea ssp. oleifolia, but it will need checking and re-checking! I noticed one strium on the small section of last year's wood I remembered to collect.

Osiers at Leybourne Lakes

Leybourne really is a magical place, despite the pipeline they are putting in across the site by the "Ocean" lake at the near end, and the new paper recycling mill being constructed at the far end of the lakes by the river.

I was trying to look at the willows more carefully, separating the White and Crack Willow trees, but as I looked, it was becoming much more obvious how much Common Osier, Salix viminalis (L.), there is around the site. These are generally multi-stemmed shrubs or small trees rising to about 3 or 4 times my height, much smaller than the taller other trees of the genus here. There are reasonable numbers at the far end of the Ocean Lake, still with plenty of their long narrow leaves on at the moment, and they seem to be well held very late into the winter. The shrubs all seemed to fit straight Salix viminalis, which is common throughout most of lowland Britain, but it is quite possible that I missed some hybrids, which may be either planted as SRC or rarely found in far-away pockets of the country. Equally, some of the trees near the waters edge had good long leaves over 15 cm long, while other (smaller) trees upslope and amongst grass showed with leaves nearer 8 cm long - just due to competition or what?

The remaining leaves are long and narrow, tapering both at the tip and at the base from a thin stalk, arising from a boat-shaped insertion on the stem over the catkin-bud, linear-lanceolate (to 20 cm long) slightly wavy and almost entirely (untoothed) or completely entire, with an obviously silky hairy covering on the underside, a very obvious soft silver even from a distance, especially when the leaves were dry. The petioles are narrow, very pubescent and often partly or even wholly canaliculate on the upper side. It is difficult to see how this can be distinguished from the matted tomentose nature of Salix elaeagnos without having seen those leaves, but the so-called appressed nature of the hairs may imply they are shorter and smoother as well as being presumably laid flat in their complete coverage over the lower surface.

I couldn't see any hairs on the top of the leaves, there are reputed to be a few scattered there, but it is actually very late in the season. The stipules, when present, were linear, (reputedly often falcate) about 10 mm long. They were not however regularly (or uniformly) caducous, a feature which may just apply to the weaker shoots..

The margins of the leaves were very clearly turned down or revolute along the majority of the length, and this was particularly notable as the leaves dried over the day or two in the house before I got to look at them in detail. The margins were wavy, going up and down in the vertical plane regularly along the edge of the leaves. Some sections of the leaf margins appeared to show slight crimping as though they were showing the early stages of the gall midge attack, Dasineura marginemtorquens. There were wingless aphids commonly, evidence of leafhopper feeding, and willow rust everywhere on the undersides of the leaves.

The most amazing thing about them is that many of the leaves appeared to be twisted around so that they were almost upside down! Following the channel of the leaf base as it emerges from the boat-shaped structure branching out from the stem and almost fully covering the very gorgeously silky catkin-buds, the channel of the proximal side twists over until it is on the positionally "lower" or "outer" side of the leaf, forming a groove over the now "outer" surface of the leaf, which is morphologically the glossier top. The ridge on the distal side away from the stem equally appears on the "upper" silky-white under surface of the leaf which now appears to be held upwards or on the top or "inner" side in relation to the stem!!  This must be about being linear leaves near the stem, and needs to be checked out in the field, in case they have twisted as it dried. After checking it looked as though this was all due to the way the shoots were being held.

The stems are extremely interesting, remaining rather grey-silky until you get far enough back along the stem that the leaves have been lost, and then turning into a rather attractive glabrous and shiny greeny-olive young "multiple epidermis" as the silky hairs are lost. Lower down in the denser parts of the bush I thought this epidermis turned more towards the yellowish-brown hue. In addition you can see the first-formed buds at the base of the shoot appear now to be much more widely separated than the later formed ones near the tip, as well as being much smaller and quite dormant in appearance. Is this due to rapid shoot extension early in the season? The pith inside the shoot is filled with a quite tightly packed fibrous material, the structure of which appears to be pre-adapted to the flexible but still tough nature of the osier wands!

The silky part of the stem is pierced occasionally by beautiful low-lying (i.e. below the level of the surrounding epidermis) chestnut-red lenticels, with a central channel. As the stem matures, the corky cells in the lenticel develop and grow further, pushing the lenticel up above the level of the stem surface now covered in the developing glossy young "multiple epidermis", so that you get a tiny chestnut-red raised welt on the new surface, on which the channel is less obvious. I'd rather not call the glossy surface bark as yet!

I haven't looked at the main branches and trunks as yet. Photos hopefully to follow. The general outline of the shrubs/trees may be narrow, truncate or rounded. Growing osiers for basket making is a very interesting industry! http://www.harpenden-history.org.uk/page_id__125.aspx

It may have been widely planted in the UK, especially in N and E, and may also be an Archaeophyte, despite its widespread distribution, possibly having originated in the river systems of Russia and having been spread westward with man. It may be quite genetically uniform, fitting in with this, but may have several varieties, including one known as var. linearifolia, although this can also be created by neglect or a difficult growing environment.

Cricket bat willows

I think I've found some cricket bat willows on the far side of the River Medway to the South of the parish boundary. There seems to be a short almost avenue (although the tree to the front of the group on the left hand side is actually an oak I think). The trees to the right are what I think to be genuine Cricket Bat Willows, usually referred to as Salix alba var. caerulea (Sm.) also known as a cultivar 'Caerulea', much more upright, with branches soaring upwards at an angle of between about 20 to 40 degrees (narrower than the type) from the more or less vertical trunk (although this particular one has been cleft into two, and would certainly be useless for bat manufacture).

Here is a close-up of some more of the trees on the right, ones with straighter trunks. You can start to get an idea of the ruggedly furrowed bark on the trunks, even at this distance. They are in a fairly typical "willow" environment, with the trees' roots half in and out of the roadside ditch.

This is a closer shot of the bark at about chest height, which is described for Salix alba in the Collins Tree Guide as "dark grey; rugged, criss-crossing ridges". It sort of seems to fit, although any decision on these colours can be a real snare and delusion. In fact this bark looks to me in close-up perhaps to be a mid-brown, but largely covered in grey lichen! If so, my ID here may be at error. However good old Clapham, Tutin and Warburg have the description of the species' bark just as "greyish, not peeling, fissured, the ridges forming a closed network". Wikipedia has the bark as "greyish-brown", even better.

Making cricket bats out of the trees is not so easy, and I doubt any of these trees would be much use. Here is a clear description of how it is done.
http://www.woodlands.co.uk/blog/practical-guides/cricket-bat-willow/

And here is more information on grading clefts for bat production, including the vexed issue of grain number - http://www.middlepeg.com/cricketbatwillow.htm. The trees for commercial bat production have to be grown carefully in a controlled plantation, and are harvested at between 15 and 30 years old:

Clearly at least one thing has gone wrong with this trunk below, resulting in a whole clump of stems springing out of what might be some small bolls on the left hand side, and a definite kink in the trunk. These won't be any good for making cricket bats! Commercially produced trees have to have any small side-shoots growing out from the straight trunk rubbed out - at a very early stage!

It's interesting to make the link between the trees and the finished product, as Milton Keynes Parks Trust have done here: http://www.theparkstrust.com/downloads/plants-and-trees/general/Making%20bats%20from%20cricket%20willow.pdf

In fact almost all trees commercially produced in England are from East Anglia, the majority of which are produced by J. S. Wrights of Great Leighs, Essex. Most of the clefts are exported to the Indian subcontinent where they are turned into bats - only a very small specialist industry of bat manufacture actually remains within the UK as seen in this video - http://www.youtube.com/watch?v=yRc4QoRJDDo. Presumably then the finished bats are returned to England for sale in local shops, such as Kent Cricket Direct in Southborough.

Going back to the trees growing along the road to Hartlake, the young shoots are reddish-brown, particularly on their tops, but can look greyish in some lights - due to small short hairs covering the surface? Two year old stems are an olivaceous colour, clearly contrasting with the browner younger shoots.

Willows are also probably very useful for wildlife - here you can see what are probably beetle exit holes in the heartwood, exposed in this knotty wound. The surrounding lichens are also interesting!

This particular tree is probably also quite useful for wildlife:

And I think I may not be the only person (not surprisingly, they are SO interesting) blogging about willows!
http://blueborage.blogspot.co.uk/2013/02/willows-and-water.html