Friday, 26 February 2016

Daventry Calling

Today I visited Borough Hill, to the east of Daventry. This hill, at about 660 feet, is not the highest in the county (that honour goes to the nearby Arbury Hill at 735 feet) but its position, over the millennia, has given it considerable significance. 
A tall transmitter still tops Borough Hill,
Daventry.  26 February, 2016 

It was the site of an important radio transmitting station, 5XX, operating from 1925 to 1992, and the words 'Daventry calling...' were familiar to radio enthusiasts worldwide. It is still topped by an impressively tall transmitter (which I never succeed in photographing in the true vertical).

My visit today was unconnected with radio, the target being the belt of woodland which clothes the lower western slopes. Geologically Borough Hill consists of sands and ironstone yielding moderately acid soils and is of some interest botanically. A road takes vehicles to a car park just short of the summit but I took the gentle footpath up.

Silver Birch and gorse are distinctive. Borough Hill,
Daventry. 26 February, 2016

Gorse, Ulex europaeus, and Silver Birch, Betula pendula are native here, forming distinctive features of the landscape. The latter is common enough as a planted tree in Northants but, as a native tree, is rather rare. Other trees present were oak, sycamore and beech.

Gorse, as ever, was in bloom. Borough Hill, Daventry.
26 February, 2016

The gorse must surely be a location for the Birch Shieldbug; the plant is there is masses and, almost inevitably, was a blaze of colour.

Sycamore with, leaning to the right, beech.
Borough Hill, Daventry. 26 February, 2016

The beech (shown on the right of the photograph with sycamore on the left) I almost overlooked. Its normally elephant-grey trunk was in this case rendered green by a coating of pleurococcus. This alga is perhaps the most abundant land organism on the planet, with a population estimated at ten trillion. I was walking over to examine the large Crown Gall on the trunk before the penny dropped, with an examination of the buds confirming it as a beech. Crown Gall, caused by a bacterium, Agrobacterium tumefaciens, causes the huge bosses common on the trunks of many trees.

My bunch of keys helps to show the girth of this
cherry tree. Borough Hill, Daventry. 26 February, 2016
Beech trees in the wild (and here it is probably planted) have a taste for lime in the soil although good drainage seems to be more of a requirement. Was there a little lime in the soil at this point? I asked myself this question because, a few yards away, was a quite magnificent Wild Cherry, Prunus avium. Its girth was enormous and, as this species is definitely a native of Northamptonshire, probably occurs naturally here where it is quite a good indicator of limestone.

This Wild Cherry, Prunus avium, is moribund.
Borough Hill, Daventry. 26 February, 2016

                                                        Sadly the tree seemed to be on its last legs and, although there may be seedlings around, I failed to spot any. This cherry species is popular for planting and in decades to come its natural distribution could become rather obscure.

I left the area vowing to return, if only to look for cherry saplings, but before departing,took a long look at the panoramic - and slightly misty - view of Daventry which Borough Hill afforded. The temperature had not risen above 5-6 degrees all day and I was happy to be heading home.

Daventry, looking west from Borough Hill. 26 February, 2016

Thursday, 25 February 2016

Oaks and Erratics

Kentle Wood is bordered on the west by arable land and I had a good look at it today. I was glad to be wearing welly boots for the ground was very sticky and even a cursory examination showed that, as I had suspected, the land was boulder clay, sometimes referred to as till.

Boulder clay! Flint pebbles are a giveaway in the soil
adjacent to Kentle Wood, Daventry. 25 February, 2016
There was nothing clever in coming to this conclusion; among the cereal plants the soil was littered with pebbles and shattered lumps of flint. This is a rock not found in Northamptonshire, ergo, somehow these flints had been transported here, perhaps from Norfolk. It was over much of Northamptonshire that the last ice sheets melted at the end of our most recent ice age, and as this melting took place the burden of rock and sand embedded in the ice was dropped.

This moraine also contained 'rock flour' - rocks ground up to a material so fine that, when wet, it took on a thick, sticky consistency - clay. It helps to explain why some of the trees, fifteen years after being planted are not as tall or robust as I feel they might be; these soils, as any half-decent gardener will know, can be cold, lacking air and poorly drained.
Ouch! Motor cyclists have found a way
into Kentle Wood. 25 February, 2016

It is clear that motor cyclists have recently found an entry point into Kentle Wood and their wheels are churning up this clay in a very unsightly manner. At the moment their depredations are having little or no effect on wildlife, but if it goes on...

The cluster of brown buds at the end of a twig makes
oak easy to identify.  Kentle Wood, Daventry.
 25 February, 2016

So, although during yesterday's visit to Stefen Leys there were signs of spring, these cold soils of Kentle Wood are holding things back. Buds were almost breaking in Stefen Leys Pocket Park; in Kentle Wood the oaks, for example, are yet to show any swelling. Incidentally it is the cluster of brown buds at the end of a twig that make an oak easily recognisable.

Once seen, easily remembered. The black
buds of ash. Kentle Wood.
25 February, 2016

As for ash, the soot-black buds are also very distinctive but likewise are not yet showing any the growth that might be occurring on lighter, warmer soils. The upshot of this is that Kentle Wood is still wearing a wintry appearance and it may be weeks before things really get going.

At Badby Woods, only a couple of miles away as the crow flies, things are different. Centuries of falling leaves have been incorporated into the top soil, greatly raising the humus level and there are already encouraging vernal features to be seen. Perhaps that should be my next destination.

Wednesday, 24 February 2016

Spring is a-springing

Last night saw one of the sharpest frosts of the year, but the lovely sunshine that followed put spring in the air and a spring in my step.

Not that I went very far. I was content to walk the few hundred yards to Stefen Leys Pocket Park. A tortoiseshell butterfly flitted across my path as I entered and a flock of wood pigeons clattered into the air, scything their way across the blue sky in a frantic arc. A pair of bullfinches worked their way through the trees and a blackbird took to the air carrying nesting materials. 

Spawn of the Common Frog, Rana temporaria, formed
clumps at the pool. Stefen Leys Pocket Park.
24 February, 2016

Other creatures were busy at the generation game and the pond was alive with toads thrashing their way around, each female struggling with three or more grappling suitors. However, frogs had beaten them to it and I was pleased to see a dozen or so clumps of their spawn. The water must have been very cold during the night but no harm will have been done.

Pleasingly only the native 7-spot Ladybird was noted.
Stefen Leys Pocket Park, Daventry. 24 February, 2016
Ladybirds had emerged from their winter bolt-holes - usually a cluster of dead leaves - and were ambling about. It may be some time before aphids become available as a food source but they will subsist on their fat reserves until then. All that I saw were 7-spot Ladybirds, Coccinella 7-punctata, but it surely won't be long before the unwelcome Harlequin Ladybird, Harmonia axyridis, is on the scene.

A number of Alder trees have been planted in the pocket park.
Stefen Leys, Daventry. 24 February, 2016

Job done! Male Alder catkins are beginning
to wither. Stefen Leys. 24 February, 2016

Alder trees were still sporting their catkins but these had lost their golden-green colour of recent weeks and, their job largely done, were taking on more sombre brown tones with many of them littering the ground. The female catkins were beginning to swell too, and will soon take on their familiar cone-like form.

Buds on Beech trees are swelling. Stefen Leys, Daventry.
24 February, 2016

A few beech trees, Fagus sylvatica, are found in the pocket park. All are coppiced or occur as a low pollard. Their buds were lengthening even as last year's leaves stubbornly clung to twigs elsewhere. The rather silky-hairy leaves will soon unfold to a lovely green.

Predictably, the temperature began to drop rapidly as the sun dipped towards the west but I was uplifted by the signs of spring. As noted in other blogs, it is the day-length rather than temperature which controls many of these advances so, even if we now enter a chilly spell, things will move on.

Monday, 22 February 2016

Taking the air

I've been a bit limited in my wanderings of late. No complaints, but I was glad to have the opportunity to stretch my legs today and enjoy a bit of late winter sunshine.

All passion spent... Crocus flowers are withering.
Stefen Hill, Daventry. 22 February, 2016

Officially the first day of spring is the first of March but already many of the early crocuses are more or less over, their flowers prone on the ground. They brought to mind Robert Herrick's lines:

      Ye doe lie,
      Poore girls, neglected.

He was, of course, writing of violets, but the same sentiments apply.  Iris reticulata, together with the common garden Grape-hyacinth, Muscari armeniacum and forms of Primula polyanthus were all in bloom too. 

Prunus x subhirtella autumnalis 'Rosea'? Stefen Hill,
Daventry. 22 February, 2016

Trees with pink blossom were - probably - the Winter-flowering Cherry, Prunus x subhirtella autumnalis 'Rosea', but I lack confidence about this. There are so many other hybrids.

Similar shrubs, but with white blossom, were in bloom on waste ground beside the A45.  Given a little more warmth these may receive insect visitors but none was seen today.

This waste ground was strewn with rubbish and these lovely trees drew the attention away from the ugliness. Nevertheless I couldn't resist investigating.

Leopard Slugs by the dozen beside the A45, Daventry.
22 February, 2016

I pulled aside some discarded plastic sheeting in the hope of revealing insects such as ground beetles (Carabidae) but instead exposed a quite extraordinary gathering of slugs (What, I wonder, is the appropriate collective noun - a slither of slugs?)
The Leopard Slug. Limax maximus, under plastic sheeting.
22 February, 2016

All were Leopard Slugs, Limax maximus, and I estimate there were 70-80 of them. They are common in gardens but are generally welcome, feeding largely on dead plant material and thus helping to convert it to humus. Despite the specific name 'maximus' it is not Britain's biggest slug, that honour probably going to the black or orange Arion ater. Even so, they are very able-bodied, as my grandmother would have said.

Returning home by a slightly different route I was pleased to find Cherry-laurel, Prunus laurocerasus, in bloom and mildly shocked to discover that in some cases the petals had already fallen. Spring is perhaps a little nearer than I'd realised! 

Friday, 12 February 2016

Brighter days beckon

Forgive me if my blogs have been thin on the ground recently. With my beloved wife Chris in hospital I have been - to put it mildly - distracted. However, with news that prospects for her are bright, I feel able to put pen to paper - or at least fingers to keyboard.

Crocuses in the grassy area of St Giles' churchyard,
Northampton. 11 February, 2016
In the seventeen days she has been away spring has advanced, not in a rush, but tentatively creeping forwards between each spell of frost.  The sun was brilliant as I crossed St Giles' churchyard yesterday and hundreds of Crocus tommasinianus, formed purple-pink drifts across the grass, with the odd hoverfly feeding, probably on the pollen. In my garden at home I generally grow forms of Crocus vernus, but 'tommies', being slightly taller, are a good choice in grass and naturalise easily.

In Byfield's pocket park the leaves of Hazel and Spindle, Euonymus europaeus, are unfurling and buds on Field Maple are fattening nicely. The Spindle, although native to Northants, is introduced here. It is a shrub generally associated with limestone so it is scarce in this area. Curiously the fruits of Spindle contain the alkaloids theobromine (found in chocolate) and caffeine (found in tea). Birds readily consume the fruits!

A number of yew saplings are now found
in Byfield Pocket Park.  10 February, 2016
I was pleased to find yet another Yew tree, fighting its way up through brambles and looking strong. The pocket park now boasts several specimens, almost certainly bird-sown from the nearby churchyard  and, although Yew is doubtfully a native Northamptonshire species, they are welcome for the variety they bring. It is of limited value for wildlife with the rather scarce Satin Beauty Moth plus a couple of gall midges being among the few insects associated with it. But the fruits are much eaten by birds with, as I have previously mentioned in blogs, the poisonous constituents having no apparent effect. In this respect it is like Spindle, whose fruits are also poisonous - sometimes fatally so.

The weather forecast is for several days of chilly conditions. Dratted climate warming!

Sunday, 7 February 2016

February Fill-dyke

My grandmother's reaction to February rain was predictable: 'February Fill-dyke,' she would proclaim.

Although probably unaware of it she was quoting from Thomas Tusser's 'Five Hundred Points of Good Husbandrie' (sic), first published in 1573: 

                                           Feb, fill the dyke,
                                           With what thou dost like.

Much of the text seems to have been written in the form of rhyming couplets, easy for a farmer to remember in an age when most workers on the land were illiterate. He had a few snippets of advice for every month of the year, with January's maxim being:

                            When Christmas is done, kepe not Christmas time still,
         Be mindfull of rering, and loth for to kill.

I suspect that John Clare would have been familiar with these old quotes, and it is remarkable that - albeit slightly distorted - they should have lingered on into the second half of the twentieth century. Allowing for modern developments, some of the advice is quite sensible and at times I have heard allotment holders making comments which I suspect were based on Tusser's maxims. Of course, they were not his ideas but were distillations of many generations of experience.

The last couple of days have been very wet - as has the winter as a whole. Dykes (for which we may read 'reservoirs') should be well and truly filled ready for potential summer droughts. Nevertheless conditions are mild with Stinking Hellebore, Helleborus foetidus, having been in flower for two or three weeks. 

Corsican Hellebore flowering in the Timken area of
Daventry. 7 February, 2016

Today Corsican Hellebore, H. argutifolius, was also in flower in Daventry, with the slightly soiled tepals also suggesting that they had been out for a couple of weeks. This species is native to Corsica and Sardinia. With its rather spiny leaves it is sometimes called the Holly-leaved Hellebore. In older books it is Helleborus corsicus. 

Helleborus argutifolius in flower. Daventry, Northants. 7 February, 2016

Tuesday, 2 February 2016

Too early for bugs

I have been feeling very low recently for reasons I need not enter into but today I received a lift the moment I stepped out into the front garden and saw irises and crocuses in bloom. They have been flowering for several days but in the morning's bright sunshine they stood out splendidly.

Iris reticulata, dependable and lovely. Stefen Hill,

The iris was I. reticulata and this species, from south-east Europe and Iran, is both easily obtained and reliable. I wouldn't be without it in any of its several varieties. The yellow Iris danfordiae is delightful too but after flowering the bulbs break up to form tiny bulblets the size of wheat grains, taking years to get back to flowering size.

Crocuses leaning to face the sun. Stefen Hill, Daventry.

The crocuses (incidentally I checked to find that 'croci' is a perfectly correct but pedantic plural) were forms of C. chrysanthus but, although 'chrysanthus' means 'golden flowered', I am growing the variety 'Blue Pearl'. I will add other colours for next season.

My target was, once again, Newnham Hill, aka Windmill Hill. I have had reports of the large and handsome Gorse Shieldbug, Piezodorus lituratus, being already active in the south of England. Would they be on the gorse shrubs atop Windmill Hill? It is an exposed, windy site so I was not at all optimistic. And in any case, would I be able to spot it? The bugs in both size and colour resemble the unopened flower buds and are easily overlooked. The species adorns the cover of my much-thumbed copy of 'Shieldbugs of Surrey', by Roger Hawkins.

Sure enough, it was blowing a near gale at the top (the tail-end of Storm Henry) and toupee wearers were at serious risk of scalp exposure - and nary a shieldbug of any type was to be seen. It is a steep climb, with slopes of 45 degrees or more in places. I managed to avoid the more precipitous approaches but certainly the scramble raised the pulse rate. My doctors would have been proud of me. 

In the face of the wind photography was tricky but I took a picture to prove to myself that I'd been there.

Sometimes, on hill tops such as this, insects will congregate or assemble, generally for mating purposes. I have not visited Newnham Hill specifically to look out for this behaviour but I must bear it in mind for this coming summer. (David Bellamy claims that he once plotted the distribution of courting couples on Box Hill for a biology paper; not quite the same thing I know but...)

Anyway, with all cobwebs thoroughly swept away I cautiously descended the hill, making it to my car without mishap.