Westhorpe Lane

I regard Westhorpe Lane as the most attractive area in Byfield and I suspect that many of the villagers would agree with me.  Once a separate hamlet Westhorp, as was an original spelling, is now merged with Byfield but retains a slight air of separateness with lovely, set-back houses, and no through traffic.

With Byfield Pocket Park incredibly wet following prolonged rain I decided to take a break from routine and stroll along the winding road, on either side of which Westhorpe stands.

Clumps of Pellitory of the Wall, Parietaria diffusa, were clustered around the base of several walls and I might have passed by these rather dull plants without a second glance. However I did pause and was rather surprised to see that there were flowers present.

Pellitory of the Wall is very common at the foot of old walls.

Westhorpe Lane, Byfield. 27 November, 2019

True they were tiny and lacking any distinctive coloration but at this time of the year any flowers are welcome. This often-neglected species is a member of the Nettle Family, Urticaceae and is often attacked by the insects and fungi which afflict its larger relatives, but these specimens appeared to be largely free of problems. Incidentally, the word pellitory is ultimately derived from the Latin parietis, a wall. Perhaps it has occupied its distinctive location since ancient times. (Another, unrelated plant, Anacyclus pyrethrum, is known as Pellitory of Spain.)

Pellitory of the Wall has flowers which are easily overlooked.  Westhorpe,
Byfield. 27 November, 2019

In a similar position at the foot of walls were Red Valerian plants, Centranthus ruber. They were being attacked, most obviously by the psyllid bug, Trioza centranthi, which was causing leaf rolls on the edge of foliage. This insect was regarded as rather uncommon up until a few years ago but now many records are coming in: either the insect has become more common or people have been alerted to look out for it.

Trioza centranthi is common locally on Red Valerian.

Westhorpe, Byfield. 27 November, 2019

On to Wistaria Cottage. To give the spelling 'Wistaria' to this lovely climber is scientifically wrong and yet it could be argued that this is correct, for was named after Casper Wistar, professor of anatomy at the University of Pennsylvania.

 

Wrong? Perhaps, but an easy mistake to make.

Westhorpe Lane, Byfield. 27 November, 2019

Thomas Nuttall, who named the plant Wisteria seems to have got the spelling wrong but, according to the International Code of Botanical Nomenclature, the original spelling must stand.

Our native Wild Privet, Ligustrum vulgaris, grows along Westhorpe Lane. Privets are members of the Olive Family, Oleaceae, and its small, glossy black fruits do have a passing resemblance to tiny olives. They are still present in some quantity, apparently being eschewed by birds in favour of tastier fare.

Wild Privet, as it is usually unclipped, bears fruit in quantity.

Westhorpe Lane, Byfield. 27 November, 2019.

The leaves are distinctive, being almost lanceolate in shape. This make the species easily distinguished when compared to Garden Privet, Ligustrum ovalifolium, some specimens of which also grow along Westhorpe Lane.

The leaves of our native privet are almost lanceolate.

This latter species is from Japan and Korea. Its leaves are, as the name indicates, far more oval in shape. Both species are semi-evergreen, managing to retain some of their leaves in even the harshest winters.

Japanese Privet has leaves far more oval in shape. Westhorpe Lane, Byfield.

27 November, 2019

Fishbone Cotoneaster, Cotoneaster horizontalis, was in fruit, occupying its usual position against a wall. This Chinese species was introduced to Britain in the late 1870's and can be very invasive, frequently being found in the wild. It does however have two redeeming features: its flowers are very attractive to bees and its fruits are popular winter feed for birds.

Cotoneaster horizontalis is a very popular garden plant. Here it is in

Westhorpe lane, Byfield. 27 November, 2019

I will mention only one other plant. The Japanese Quince, Chaenomeles japonica, was displaying its pale yellow apple-like fruit. It is a low-growing shrub, easily confused with C. speciosa, a rather taller plant. (The true quince is Cydonia japonica.)

Japanese Quinces stood out boldly on a miserable, damp day.

Westhorpe, Byfield. 27 November, 2019

Theoretically the fruit can be eaten but they are hard and astringent unless allowed to go semi-rotten, a process known as bletting. The books will tell you that it may be used to make quince jelly but I have never found anyone who has attempted this. It is grown instead for its spring flowers which may red, pink or white.

I turned to go home and in so doing lost my footing on a grassy, muddy bank, landing with a bump. 'Oh dearie me!' I muttered...and spent the next few minutes scraping mud from my shoes. However I made my way without further mishap to my car. Foolish man!

Of headaches and worms

Lovely racemes of Mahonia greeted me as I parked up at Byfield Village Hall. There are about 70 members of the genus found in North and South America together with South East Asia. Hybridists have been hard at work on these plants and so many varieties are available that to put a name to a particular plant can be tricky but for my money this specimen is the very popular 'Charity', a hybrid between Mahonia oiwakensis and M. japonica.

Mahonia, probably 'Charity', beside the village hall in Byfield.

20 November, 2019

Its name provides another example of a person who would otherwise have been forgotten had it not been perpetuated in this way For the record, Bernard M'Mahon was an American horticulturalist about whom little more can be said. And, speaking of names, M. japonica is not a native of Japan, although it has been cultivated there for centuries.

I strolled down to the pocket park, passing some rather bedraggled specimens of Feverfew, Tanacetum parthenium, growing on a grassy bank near the home of our friends Damien and Lynda Moran.

Feverfew was doing its best to look cheerful on a grassy bank in Byfield.

20 November, 2019

It is a good example of a plant which was first introduced as a medicinal plant (still valued for the treatment of migraine) but whose attractive flowers gave it horticultural merit. Several forms are now available including those with 'double' flowers (flore pleno) and others with golden-yellow leaves. Its original home is the Balkans but it is now found worldwide as a weed.

On then to the pocket park. I paid more attention to the plants of Male Fern, Dryopteris filix-mas, it the hope of finding evidence of galls or leaf miners but there was nothing doing.

Male Fern, Byfield Pocket Park

If Feverfew is valued for the treatment of migraine, the Male Fern is - or was - once used as a vermifuge. Gerard wrote: 'The roots of the Male Fern, being taken by the weight of half an ounce, driveth forth long, flat worms...(but) they that would use it must first eat garlic.' At one time it was widely used by vets for expelling tape worms, and perhaps it still is. For those who feel the need to partake of this remedy there is also a small clump of Wild Garlic (Ramsons) in the pocket park. Bonne chance!

Lichens on an oak branch. Byfield Pocket Park, 20 November, 2019

Trees were nicely encrusted with lichens but the remainder of my time in the pocket park was spent in the search for leaf miners. I was rewarded with several items but I'll spare readers the details on the grounds that they could cause dislocation of the jaw through yawning.

Deceptive weather

Following my last visit to Foxhill Farm I found that my list of invertebrates recorded there totalled 499. There was no way that I could leave things like that so today, with the weather dry and sunny, I set out. However, conditions were deceptive and a brisk north wind soon reddened my nose and cheeks.


I sloshed my way through wet fields and tried my luck beneath a stand of Coast Redwoods, Sequoia sempervirens, but with little success. Where wooden fences were sheltered and sunny a few common flies such as Calliphora vicina were gathering. The Calliphora is one of our commonest blowflies and was well recorded. So no luck there.

Perhaps the lichens are of more interest than the fly, here basking in

morning sunshine. Foxhill Farm. 18 November, 2019

Foxhill Farm consists of one large spread of about twenty fields, all given over to sheep. However, another two fields are separated from the main spread by the Daventry to Newnham road. I had briefly visited these fields, also consisting of sheep pasture but, seeing nothing of obvious interest, did no recording. Today I decided to put that right.

Some Bracken, Pteridium aquilinum, was growing through a hawthorn hedge. On the rather acid soils of this region Bracken is common but little grows on Foxhill Farm and, as it can sometimes bears interesting galls and leaf miners, I made a mental note to give it some attention next year. Bracken contains a toxic carcinogenic compound and it is surely not a coincidence that Japan, where the young shoots are eaten as a vegetable, has some of the highest stomach cancer rates in the world.

Bracken thrives on the mildly acid soils of the Foxhill Farm area.

18 November, 2019

Blackberries were still ripening although whether they will be able to complete this process with winter approaching is doubtful. If they do ripen they will be eagerly seized upon by hungry birds.





Have they left it too late? Blackberries still ripening at Foxhill Farm.

18 November, 2019

Nearby I was pleased to find a couple of Giant Puffballs, Calvatia gigantea. It is a species that seems to do well on pasture land, perhaps because this land is often rich in phosphates.

Not gigantic, but a satisfyingly large pair of giant puffballs.

Foxhill Farm, Badby, Northants. 18 November, 2019

A better idea of scale is provided by the second photograph, where a sycamore leaf (complete with tar spot fungus) is present. The two specimens weren't particularly large for a species where large specimens have apparently been mistaken sheep (should have gone to Specsavers) but they were impressive enough.

Slugs and fungus flies will soon get to work on it.

An interesting fungus was growing on a rotting gatepost. I suspect it is a Honey Fungus, Armillaria mellea. Honey Fungus is apparently a group of closely related species, tricky even for an expert. As a tyro in this field I'll just refer to the genus sensu lato. 

Honey Fungus (?) on a gatepost at Foxhill Farm. 18 November, 2019

Had I reached 500 species? Just prior to leaving I lifted a sheet of corrugated iron beside a shed to reveal several money spiders and these may include the required extra specimen although, let's be honest, it is only a number. Watch this space.


Postscript  As hoped, these money spiders included the tiny, pale Palliduphantes pallidus. Five hundred up!

Yet more rain

Early November has been exceptionally wet and when I visited Foxhill Farm about three days ago much of the ground was saturated. Since then there has been more heavy rain and around Byfield there has apparently been extensive flooding. Although I have been anxious to get out and have a look I have been tied up with other things. The land often drains quickly - nice for those directly affected but frustrating for those, armed with a camera, who are keen to see for themselves. The situation is exacerbated by the shortness of the days, with darkness upon us by five in the afternoon. In my childhood flooded fields would attract snipe and other waders but such visitors are now seldom seen.


When I finally went to Byfield to have a look the water levels had dropped considerably. The stream which passes though the village, a tributary of the Cherwell, was still carrying about double its normal flow but was now safe within its banks.

This stream apparently has no official name but is sometimes locally called

the Brightwell Brook. Byfield, 17 November, 2019

The churchyard - to the right of the picture - is rather untidy but carries little of botanical interest although, to be fair, some of the trees support moths, flies and true bugs worth checking out.

Field Horsetail in the grounds of Holy Cross Church, Byfield.

17 November, 2019

Sprawling through the fence are some tangled clumps of horsetail. In Britain we have several species (about 12) of these curious plants and in this case the plant present was the very common Field Horsetail, Equisetum arvense. This species is a weedy plant, sometimes a problem in cultivated ground and very resistant to herbicides. It grows to a maximum height of about 30 centimetres but in Carboniferous times, some 300 million years ago, their relatives, Calamites species, would reach 30 metres and their remains form an important element of our coal seams. If a bunch is passed through the hand it feels very rough, due to the presence of silica spicules. This once made it highly valued for the polishing of hardwoods, ivory and brass. I am told that some woodwind players still use it to shape and scrape their reeds. It may be valued for use in some crafts but is not welcomed by farmers. The highly abrasive silica is a problem if it is consumed by livestock but a toxin, Thiaminase, is also present. I never eat it.

What of flowers? Well, unsurprisingly there were few around. The most obvious was Greater Periwinkle. Vinca major. It is not a native (in fact none of the family to which it belongs, the Apocynaceae, is native to Britain) but belongs to the Mediterranean region. It is quite well established in places but the Lesser Periwinkle, Vinca minor, despite being introduced to Britain long before its greater cousin is less aggressive and not commonly found outside gardens.

Periwinkle in brave - and probable futile - flower.

Byfield, 17 November, 2019

Periwinkles are also poisonous but only mildly so, although its close relative, Catharanthus rosea, once known as Vinca rosea, contains some rather dodgy alkaloids (notice the precise medical terminology) which have been used in chemotherapy.

Vinca major seems remarkably resilient and is frequent in hedgebanks and shrubberies in the south of Britain. It is related to Oleander, Nerium oleander, and the Oleander Hawkmoth may, if you are very lucky, be seen visiting periwinkle flowers, but this striking insect is a rare visitor to Britain.  

Dog Walking

Dean (our son-in-law) has been in hospital today and Jacqui has been on a course and so Chris and I have looking after their dog. No problem as I was planning to walk around Byfield Pocket Park anyway. I knew Bing would enjoy the visit too.


To be honest Bing isn't much of a botanist and his entomological knowledge is distressingly limited, but I try.


Hazel bushes hold their leaves very well and were showing the mines created by the Nut Leaf Blister Moth, Phyllonorycter coryli. This is very common and I have seen it in the park on many occasions so I was surprised to find, on checking, that I'd not recorded it before.

The blister-like mines of Phyllonorycter coryli on hazel leaves.

Byfield Pocket Park, 13 November, 2019

The leaves of many other trees and shrubs have fallen or, if they have not yet done so they have largely taken on autumn colours. One plant not generally noted for autumnal coloration is the common Bramble, Rubus fruticosus agg. Today however I found some attractive examples. These colours are probably confined to just a few microspecies within the aggregate.

Bramble leaves can sometimes take on attractive autumn colours.

Byfield Pocket Park, 13 November, 2019

Northamptonshire is not a county noted for a rich fern flora and, partly as a consequence of that, my own knowledge of these interesting plants is very limited. Perhaps the commonest fern in the county is the Male Fern, Dryopteris filix-mas.

The Male Fern is a graceful plant and sometimes tempts people into

removing them for their gardens. Byfield Pocket Park, 13 November, 2019

The pocket park contains many specimens although I suspect some have been dug up to grace local gardens. It can be distinguished with reasonable ease by the rounded reproductive organs, the sori, on the underside of the leaves. Each 'leaflet' on the fronds bears between three and six of these structures which are generally  pale brown. On the related (and less common) Broad Buckler Fern, Dryopteris dilatata, the sori are spaced further apart.

The pale brown sori on the fronds of the Male Fern are reasonably

distinctive. Byfield Pocket Park, 13 November, 2019

I tried pointing this out to Bing but she was more interested in the intriguing smells of the woodland floor.

Nearby were some bushes of Spindle, Euomymus europaeus. Whenever I see a specimen I am unable to resist a photograph. I suspect this is because as a child I never saw one, the heavy neutral clays around the northern fringes of Northampton apparently not favouring this species. It prefers calcareous soil and as an undoubted native in our county is not particularly common (John Clare apparently fails to mention it) although it has been extensively planted. There is a very old record of it, presumably as a wild plant, from the Charwelton area.

The fruits of the Spindle tree have now largely split. Byfield Pocket Park,

13 November, 2019

The contrast between the lipstick-pink outside of the fruit and the bright orange coating of the seed is quite striking. I forgave Bing's lack of interest as the recognition of colour by dogs is very limited. I hope she reciprocates by overlooking my limitations with regard to smells.

Precipitation and pansies

My forays into the blogosphere have, of late, been few and far between. I have found a foolproof way of guaranteeing rain: make plans for a walk. The amount of rainfall lately has been prodigious. I went out to change the seed in one of our bird feeders only to find that an earlier batch, clearly of wheat, had germinated.

Seed has germinated in one of our bird feeders. Stefen Hill, Daventry.

10 November, 2019

Getting the lawn mower out to deal with it was an absolute bugger!


It has been cold too, and we awoke a couple of days ago to find every roof white with frost.
 

The gardens are NOT at their best, with flowers almost non-existent. There are a few flowers on the Regal Pelargonium, Pelargonium grandiflorum, but following the frost the plants may be moribund. The nectar guides on their petals stand out boldly but few insects will be using them.

The nectar guides are very obvious on this regal pelargonium.

Stefen Hill, Daventry. 10 November, 2019



Speaking of nectar guides, they are very distinct on the only other flowers currently present in our garden. I refer to the pansies in one of our hanging baskets.

Curious plants, pansies. I have always felt that they have a vague resemblance to Busy-lizzies (Impatiens species) but alas, on checking it seems that no one else accepts any relationship. They take their name from the French pensee, a thought (pensive comes from the same root).

Against a yellow background the nectar guides on pansies stand our clearly.

10 November, 2019

Several species of Viola have been used to produce our large-flowered garden pansies, but Heartsease, Viola tricolor, has made the largest genetic contribution and the generally accepted Latin name for our garden pansies is Viola tricolor var. hortense. The genus should be pronounced not like the musical instrument but as Vi'ola, with the accent on the first syllable. (But if people get it wrong, who gives a monkey's chuff.*) Heartsease seems to be a good example of the Doctrine of Signatures: God - or the gods - has given us humans signs indicating how the plants should be employed, with the heart-shaped leaves suggesting that the plant could be used to ease heart problems; lungwort has blotches on the leaves to suggest diseased lungs, and so on. However, although herbalists have used the pansy in many ways, from reducing flatulence to making a lotion for bathing sore eyes, it does not seen to have been used for heart problems (or it may have been used before deciding that it was ineffective.)

In the height of summer I see the occasional insect visit garden pansies including ladybirds feeding on the numerous aphids which may gather on them, but the plants are not likely to feature in a garden designed with wildlife in mind. In the open countryside it is a different picture with several butterflies depending on viola/pansy plants in the caterpillar stage. About six species of fritillary butterflies in the U.K. including the High Brown, Pearl-Bordered and Silver-washed are found on wild violets but whether they occur on garden pansies I doubt. If your pansies have been eaten then snails and slugs are the likely culprits. In their hanging baskets our pansies should be beyond the reach of these voracious gastropods.


Daffodils and croci are pushing through but we have a few weeks to wait for flowers.

* chuff. A very rude dialect word originating in the north of England, referring to a lady's er … birth canal.

Naught for your comfort

Well, perhaps that's overstating it a bit, but it has been a dull, dank and dreary day - and cold too. Nevertheless, I could not leave custom undone so I made my usual Wednesday morning trip to Byfield Pocket Park.


Hogweed Hotel was open for business but was receiving few visitors. Can't blame them, for any nectar would be greatly diluted by the overnight rain but basically insects, being ectothermic creatures, need the warmth of the sun to lift them from their overnight torpor.

No takers today. The hogweed, so popular with insects, was free of

visitors. Byfield Pocket Park, 6 November, 2019

It was a day for birds, and had I brought my binoculars I could have noted a number of species. So far the autumn has been easy for birds, with shrubs and herbaceous plants still bearing heavy crops of fruit, as yet unrequired.


Tutsan, Hypericum androsaemum, was covered in fruit, but in truth these will not currently attract birds. The fruit will eventually split and expose the seeds upon which birds, particularly bullfinches, will feed. Tutsan is an odd sort of name and is apparently derived from the French toute-saine - meaning 'all-heal' and the plant once had a reputation as a healing plant. Rather oddly perhaps, tutsan leaves were once traditionally used as bookmarks, particularly for bibles. The hypericums are otherwise known as St. John's Worts.

One the fruit have split open these tutsan fruits may attract seed-eating

birds. Byfield Pocket Park. 6 November, 2019

Also untouched were the berries of Guelder Rose,Viburnum opulus. The specimen I photographed is the yellow-fruited form, 'Xanthocarpus', and birds such as mistle thrushes may eventually feed upon them.

Beech leaves were bearing a number of leaf mines and I must make a return trip to photograph and gather a few examples, but for today I contented myself with Acalitus stenapsis, a mite which had caused the development of a neat roll along the leaf edges. It was not a new record for the site and is indeed common over the whole of southern Britain.

Neatly edged beech leaves, the work of a mite, Aculitus stenapsis.

Byfield Pocket Park, 6 November, 2019

I had sprung a leak in my footwear and so I headed back to meet Chris and friends at the Coffee Club, but I could not resist photographing some primroses on a grassy bank. These are undoubtedly the Common Primrose, Primula vulgaris, but presumably a selected strain for autumn flowering.

Yes, primroses flowering in autumn. But by so doing they will miss

pollinators such as the Dark-edged Bee Fly. Brightwell Playing Fields,

Byfield. 6 November, 2019

And finally, just before reaching my goal of the Village Hall, a specimen of Gladwyn, or Stinking Iris, Iris foetidissima, had to be pictured. As I have mentioned before, its berries seem not to be relished by birds but, given a wintry spell of weather, there may be some takers. In fact there are plants scattered around the village and this may be the result of birds distributing the seeds through their faeces.

Stinking Iris, Gladdon, Gladwyn, Roast-beef Plant. There are plants

scattered all around Byfield. 6 November, 2019

The word 'Gladwyn' is an old name for sword and refers rather obviously to the leaves. This unusual iris is rather uncommon as a genuinely wild plant but has found a congenial home in churchyards and on roadsides. I am always pleased to find it but I tend to leave it alone: it has a reputation as a very strong laxative!



A golden day

A golden autumn day - an overworked term but fully justified today. It was not just that the leaves were golden on the leaves but the quality of the light was wonderful. I didn't want to waste it but had no wish to go far, so I just visited Stefen Hill Pocket Park - where else?


A number of plants in the park  - probabyl most - have either been deliberately planted or are garden escapes. Nevertheless they are always worth checking over, with a garden rose being the first thing to catch my eye today.

Rose leaves mined by - what else? - the Rose Leaf Miner.

Stefen Hill Pocket Park, 4 xi.2019

Its leaves were covered in squiggly mines, mostly near to the leaf margins, and were the work of the Rose Leaf Miner, Stigmella anomalella. This tiny, and very common insect had, unsurprisingly, been recorded from this location before. 


An alder, Alnus glutinosa, proved to be rather interesting and I spent several minutes examining the leaves, catkins, etc. The ovoid female catkins have been pollinated and late winter-early spring the resultant seeds will be shaken out of these 'cones' by the wind. The tree is a native of wet woodlands and river banks; the seeds are adapted for these conditions, with each one containing air-tight cavities allowing it to float to a suitable germination site.

Female catkins (to the left) on the slimmer male catkins of alder.

Stefen Hill Pocket Park, 4 November, 2019

The thinner purple-brown male catkins are also present and will plump up prior to releasing their pollen on to newly-developed female catkins in late winter - early spring.

The alder leaves bore the blotch mine of Heterarthrus vagans, made distinctive by the disc-shaped cocoon, usually near to the leaf edge. It is a species of sawfly and though reasonably common is new to the pocket park.

The circular cocoon of the sawfly Heterarthrus vagans, is here clear to see

Stefen Hill Pocket park, 3 November, 2019

Numerous other insects were around including shield bugs. Several specimens of Parent Bug were present on the alder, one of their main food plants.

A Parent Bug, its parenting responsibilities now over, on an alder leaf.

Stefen Hill Pockey Park, 3 November, 2019

Green Shieldbugs, Palomena prasina, were also present. Throughout the summer they have been bright green but they are now assuming their brown coloration in preparation for the winter where, among dead leaves, they will be inconspicuous.

Many Green Shieldbugs have now assumed their cryptic winter colours.

Here on ivy, Stefen Hill Pocket Park, 3 November, 2019

Flies of various genera - Pollenia, Dasyphora, Calliphora, etc were around. I collected a few specimens but am not expecting anything new amongst them. However, on sorting my specimens I found a male of the so-called Gossamer Hoverfly, Baccha elongata, new for the park.



Hornbeam

At this time of the year Hornbeam, Carpinus betulus, is particularly attractive. The foliage is, frankly, rather ordinary. I photographed some examples earlier today at the edge of Byfield Pocket Park.

The foliage of the Hornbeam is not exciting. Byfield Pocket Park.

3 November, 2019

It is the female catkins which catch the eye. Each fruit, which is technically a nut, is held within attractive bracteoles. Now, in early November, they have taken on a pale golden colour and they hang in tassels which I find most pleasing.

But the tassel-like female catkins are a different matter.

A closer view gives a glimpse of the details, the bracteoles and nuts being clearer (perhaps).

A closer view. Byfield Pocket Park, 3 November, 2019

Is hornbeam a native of Northamptonshire? Despite the comment by John Gerard, who wrote, in 1587: The Hornbeame tree groweth plentifully in Northamptonshire,  its status in our county is unclear, and precisely where Gerard saw it growing 'plentifully' is equally unclear. (Ref. 1.) There is no doubt it is native in Epping Forest and the south-east of England. It attracts a handful of leaf mining insects and galls but so far I have found none, perhaps indicating a non-native status. Elsewhere it has certainly been widely planted, perhaps initially for its very hard wood, which was used for cart axles, cogs, spindles and so on.

More recently it has been extensively as a street tree, particularly in the very attractive form 'fastigiata', and  can be seen in Banbury, Daventry and indeed across Britain.

In its fastigiate form, hornbeam is extensively planted as

a street tree.

It has occasionally been given its own family as the Carpinaceae, (Ref. 2 for example) but today is generally included with the hazels in the Corylaceae.

References

1. Gerard, John.  His 'Herball' was published in 1597.

2. Anon (Revised 1974)  Hilliers' Manual of Trees and Shrubs. David and Charles