As I mentioned here recently, there’s a plan to change the classic botanical name of the Welsh poppy, Meconopsis cambrica. Chris Grey-Wilson, the world’s leading expert on Meconopsis, first proposed the idea of restricting the name Meconopsis to the Himalayan poppies in the botanical journal Taxon in 2012. He repeats the suggestion in his stunning new monograph on Meconopsis, which was published recently, and proposes a new botanical name for the Welsh poppy.

Actually, what he says, basically, is this: if you apply all the legitimate and agreed botanical rules, the Welsh poppy is in fact the only true Meconopsis. All the Himalayan blue poppies that have captured our imagination for so long are, botanically, so very different that they need a genus of their own. Fair enough.

But, because all the blue poppies are so fabulous and so well known to gardeners, we should call them Meconopsis and call the Welsh poppy something else. Technically, the Welsh poppy should probably be put back into the genus Papaver, where our old friend Carl Linnaeus first assigned it back in 1753. But, for various botanical reasons I needn’t go into, that would mess up the taxonomy of the seventy or so other species of Papaver. So Christopher suggests creating a new generic name: Parameconopsis. The Welsh poppy would become Parameconopsis cambrica.

He says that continuing to call the Welsh poppy Meconopsis cambrica and creating a new name for all the others “would be widely deplored in the botanical and horticultural worlds”. I wonder…

I’m entirely happy to accept that the two need to be separated. But, frankly, it sounds to me as if he simply wants to give the everyday, easy-to-grow, self-sows-everywhere plant a new name and retain the well known name for the tricky-to-grow ones with all the exotic and romantic Himalayan associations.

So I thought it would be interesting to see what the Welsh thought about all this and I asked Simon Goodenough, Curator of Horticulture at The National Botanic Garden of Wales.

“The Meconopsis debate has begun here in Wales,” he told me, “and there are a number of people who disagree with the idea of changing the botanical name of the Welsh poppy. However, I think changing its name will be a great opportunity to raise its status as a unique plant and one which Welsh botanists, gardeners and the people of Wales can be proud of. The National Botanic Garden of Wales will celebrate this change, however it plays out.” So, “always look on the bright side” is the message. Rather clever, actually…

As I said, it’s not the first time the Welsh poppy has had a change of name. Our old friend Carl Linnaeus named it Papaver cambricum back in 1753, but then in 1814 a botanist called Louis Viguier separated it out into a genus of its own. You see why here. It’s also been classified as an Argemone, a Cerastites and a Stylophorum – but let’s not dig all that up. Now, it’s going to be Parameconopsis cambrica. But I have the feeling that when someone finally takes a good long look at the whole poppy family it might be on the move again.

Oh, and in case you’re wondering… Gardeners in Britain and in North America can order seven different forms of the Welsh poppy, whatever its botanical name, from Plant World Seeds - including this double orange.

It’s purple loosestrife season here in Pennsylvania. Swamps and other wet habitats are vivid in its purple coloring (above, click to enlarge), in some places it looks as if it’s smothered everything. This colourful European native is generally viewed as a destructive menace and many millions of dollars are spent every year in a futile attempt to eradicate it.

In Britain, by the way, where purple loosestrife (Lythrum salicaria) originated, it’s far less common and is a popular plant for bog gardens with over a dozen named varieties, two of which have been awarded the prestigious Award of Garden Merit by the Royal Horticultural Society.

In North America, purple loosestrife is generally regarded as evil but part of its reputation derives from the simple fact that it’s so colorful, it’s so obvious that it’s there. If it had dull brown flowers no one would notice. Ken Thompson, in his important book that I reviewed here recently, put it this way: “Very tall people with red hair, big tattoos and conspicuous facial scars rarely have successful careers as bank robbers, and purple loosestrife has a similar problem: it’s just too conspicuous for its own good.” He goes on to emphasize: “Recognition of loosestrife as a problem was largely based on anecdotal observations, which are likely to be particularly unreliable in the case of a tall species with such bright, obvious flowers. This is a well known problem that standard textbooks warn against: it’s easy to conclude that an otherwise rather dull wetland has been completely taken over if you look at it when loosestrife is in flower…, even if a more careful examination would reveal no such thing.”

My local experience indicates that it does not necessarily spread once the first plant arrives, and that it can also decrease over time. On the lake where we live, I spotted two plants growing together about ten years ago. I checked the whole lake last week and those two plants are still the only ones present in spite of there being many suitable habitats all along the margins. Native swamp loosestrife, Decodon verticillatus, is far far more aggressive.

And in the swamp where I first saw it flowering colorfully it has declined, as it has elsewhere, and a striking feature is that native shrubs including dogwood (Cornus) and arrowwood (Viburnum) are establishing themselves on individual clumps of purple loosestrife.

And it’s not as if purple loosestrife is entirely useless for wildlife. It’s been shown that a number of native species are more likely to grow in habitats containing purple loosestrife and in a study of over 250 plots it was found that there were more birds in those with purple loosestrife than in those without. I’ve seen around thirty individual butterflies on one plant and over sixty insect genera use it, including adult monarchs (left, click to enlarge). Birds even nest in it. Another significant study that looked carefully at this issue found that there was no difference in species richness between plots with and those without purple loosestrife.

Ken Thompson says, as he concludes his discussion of the issue: “Persecuting loosestrife is, and always has been, a waste of time.”

I was tempted to pull out those first two plants that appeared at the far end of our lake but I just left them and kept an eye on the situation. Ten years later they’re doing no harm.

Don’t get me wrong. I’m not saying that anything and everything that could be, and is, invasive should just be left alone. What I am saying is that it’s not as simple as “native good, non-native bad”. Especially when you look at how fast US native swamp loosestrife (Decodon verticillatus) can spread and the monocultures that result.


Monarch butterfly on Purple Loosestrife (Lythrim salicaria). Image © Liz West (http://www.EWestPhotos.com). Used here under Creative Commons Attribution 2.0 Generic License.

In Britain, this invaluable book is subtitled The Story and Science of Invasive Species; in North America, the more provocative subtitle is Why Invasive Species Aren't All Bad. Both are appropriate; look dispassionately at the science and it’s clear that invasive species are not all bad.

So often, discussions of the whole issue of natives and non-natives (plants, animals, insects and the rest) are run through with the repetition of bold assertions, unproven by science, that it’s a relief to find a book in which the whole issue is viewed more calmly, in a broad context, considered over time, and backed by solid science. It's just what we need: more unbiased science and less thoughtless hysteria – and that is what this book provides. And it’s all presented in a lively, and very readable.

Ken Thompson discusses how we define “native” and how we stretch our objective definitions to take account of subjective impulses; he reveals how little we actually know about so many non-native species and how very few ever cause problems; he examines whether the most hated invasive species really are as destructive as we’re told and points out that some have positive impacts; he discusses how natives and non-natives can happily co-exist in the same habitat; he applies science to the myths surrounding invasive species.

One of the striking features of the response to the presence of non-native plants, in North America in particular, is the frequency with which they’re simply removed – just in case – rather than studied. As Dr Thompson points out, the proportion of non-natives that arrive in natural habitats and end up causing problems is minute. And when non-natives are studied over the long term, we sometimes find that their initial dominance is followed by a sharp decline followed by a stable balance.

I won't steal the author’s thunder by summarizing his invaluable discussion of how we define the word “native”, except to say that picking any date as a cut-off point after which an arriving species is declared an alien is clearly arbitrary and ignores the fact that ecosystems have always evolved over time and continue to do so. And suggesting that only new arrivals in natural habitats that are unassisted by man can be classified as “native” ignores the obvious fact that nowhere on the planet is unaffected by man’s influence, so nowhere is genuinely “natural” anyway.

So. What a refreshing book and one that’s full of stimulation and reminders to look at the evidence and not listen to the hearsay. This book effectively skewers the prejudices and pseudoscience of the plant police extremists for whom natives are, by definition, good and non-natives inherently bad. It should be read by anyone with an interest in native and non-native plants, by those working in the field, and also by natural history and garden writers like me - so we don't simply repeat misconceptions in our work. The book is stimulating and refreshing: as soon as I got to the end I immediately started again at the beginning. [The anwser to the book's title, by the way, is a fascinating one. Needless to say, it's not what you think.]

Where Do Camels Belong?: The story and science of invasive species by Ken Thompson is published in Britain by Profile Books. It will be published in North America as Where Do Camels Belong?: Why Invasive Species Aren't All Bad by Greystone Books in September. North American readers who are eager to read it before September can order the British edition from amazon.com.

           

Out walking in the woods again yesterday, and I found ten clumps of hellebores! They look to me like a form of green hellebore, Helleborus occidentalis, with unusually large flowers; there was one very prolific clump (above, click to enlarge) and the rest were smaller, with some clumps too small to be flowering. All were scattered across an open east facing bank. Now hellebores are not native to North America – so what were they doing there? A couple of miles from the nearest house.

Actually, it was pretty obvious. The bank was at the edge of an unusually flat area; other non-natives were around including dense thickets of forsythia (below, click to enlarge - usually a sign of an old homestead), broad patches of Japanese pachysandra (Pachysandra terminalis) and bugle (Ajuga reptans), and three individual grape hyacinth (Muscari botryoides) bulbs with a single spike of flowers on each.

I’d say it was the site of an old homestead and this was confirmed by the fact that the whole area was relatively open compared with the surrounding forest. There was also what seemed to be the remains of a stone built water cistern, sunk in the ground and partially overgrown. And the trail along which I’d been walking when I spotted the hellebore clumps in the distance turned out to be a paved road that had been closed and become overgrown.

So, even though there was no sign of tumbledown walls, at some point in the past there must have been a house there and either the timber construction had simply rotted away or it been removed to be used again elsewhere. Helleborus occidentalis has a number of medicinal uses so it’s not surprising to see it on such a site.

Still – flourishing hellebores growing in the Pennsylvania woods 3000 miles from their native home in western Europe (including Britain) was quite a sight to see. Of course there are some people who’d have them ripped out as “invasive aliens” – see my recent piece on snowdrops. So I’m not going to say exactly where they are!

At least when you see this plant by the side of the road, the answer to the question: “What’s that doing there?” is clear. This is soapwort, Saponaria officinalis, growing by the roadside here in Pennsylvania and since earliest times it’s been used to make soap.

Found wild in Southern Europe, and growing over much of Britain but perhaps native only in the south west (the botanists seem undecided), this pale form is the one seen in here in PA though in some areas a darker rose pink form is seen, and a pale semi-double form (‘Rosea Plena’) also sometimes establishes itself in the wild.
It was brought to North America by colonists specifically for its use as soap and for use in brewing, and long ago escaped from homesteads. It can be made into a very gentle soap - it’s said to have been used to clean the Bayeux Tapestry - and there’s little in the North American native flora that will do the job, especially in colder areas. Soapwort is hardy down to zone 3 (-40C/-40F). Boil it in rainwater to create a mild soapy lather. It’s been used to help create a head on beer, and is also used to make halva.

To be honest, the plant is a bit of a thug, even in poor soil it grows vigorously as long as it has plenty of sun, and it takes the salty run-off from roads in its stride. In fact it’s so adaptable that it’s naturalized in every American state except Alaska and Hawaii. Here in Pennsylvania, it often grows along roadsides with double-flowered daylilies – about which more next time.

A neighbor came round to take a look at the garden yesterday, and one of the things she was most impressed by was – bugleweed (or simply bugle, as Brits say).

We have quite a few different forms, none of them in flower of course, not in July, and while she admired the prettily coloured variegated sorts like ‘Burgundy Glow’, she was especially struck by the efficient ground covering prowess of the plant in the picture (above, click to enlarge). And it’s certainly impressive.

From a single root dug up from under the satellite dish at the radio station where I do my music show every week, in five years it’s spread to this dense covering about 5ft x 6ft. The only plants to penetrate are self sown helleborine orchids.

But this is not just any old bugle. The reason I dug up a little piece in the first place was because it looked so dramatic with tall white spikes of flowers, instead of the usual blue. In the shade under our maples and oaks, the tall spikes look wonderful in full flower. And they’re good cut for spring posies, too.

It looks as if the name for this plant is Ajuga reptans f. albiflora ‘Alba’ (right, click to enlarge) but I remember seeing a white-flowered bugle at the Chelsea Flower Show a few years ago under the name of ’John Pierpoint’ which seemed to be more compact, with much shorter flower spikes. White frorms turn up in the wild in its native Britain, occasionally, but I've only seen ever seen one spike - on a farm track near where Cream drummer Ginger Baker used to live years ago...

So, anyway, our neighbor will be receiving a batch of little parcels, small pieces of the various bugles we have around to get her started. And she’s already received a warning about how rapidly they can spread. You should see our “lawn” in the spring… More blue bugle flowers, than green grass.

There are nettles, and there are nettles.

The perennial stinging nettle, Urtica dioica, is often the first British wild plant that kids learn to recognise - because they get stung. The leaves are covered in stinging hairs which contain formic acid, histamine and seratonin. Its annual relation, Urtica urens, actually has a denser concentration of stinging hairs, but the plants are much smaller so the damage to a tumbling child is usually much less.

In the US, two native American subspecies are found as well as the European form which is naturalised over most of the country.

The stings are not dangerous, although a related species in New Zealand is rumoured to have killed horses! But they are not pleasant and come with a red rash – especailly after you’ve scratched it. The cure often grows conveniently alongside – rubbing the stung area with dock leaves, broad-leaved dock, Rumex obtusifolius, for example, takes the edge off the pain.

But also often growing with stinging nettles is white dead nettle, Lamium album (above, click to enlarge) – “dead”, with no sting. When not in flower, stinging nettle and dead nettle look alike with the similarly shaped and sized leaves gathered in pairs along upright stems.

The dead nettle stems tend to be fatter and more obviously square, but when the two-lipped white flowers open the distinction is obvious; nettle flowers come in relatively unobtrusive green tassels. Kids tend not trust the distinction.

Stinging nettles are actually very useful plants; paper can be made from the stems; the foliage is important as food and shelter for many caterpillars; the young shoots can be eaten steamed or made into soup. Nettles have also been used to treat a wide variety of maladies.

And keeping nettles in your pocket is said to protect you from being struck by lightning. Of course, if you misidentified the plant and keep dead nettle in your pocket by mistake – when the lightning strikes, dead is exactly what you’ll be.

As far as the eye can see… Celandines, carpeting the damp woods at Black Brook Park in Union County, New Jersey. We were out there the other day, taking a family stroll.

And after marveling at vast acres of skunk cabbage growing along the muddy stream, we turned a bend in the trail and, on slightly drier ground, were the celandines, like a vast green ballroom carpet scattered with yellow confetti. I don’t think I’ve ever seen so many in one place.

Lesser Celandine, Ranunculus ficaria, is a widespread British native perennial with roots like tiny dahlia tubers. Very early into growth, its waxy green leaves are topped with flowers like buttercups. Later in the season it completely dies away. The whole plant rarely reaches 8in/20cm in height. It’s common wildflower and an irritating garden weed in Britain, spreading by seed but also when the clusters of tiny tubers break up.

In North America it’s known as the Fig Buttercup – from the shape of its bright green leaves and its yellow flowers - and is becoming widespread in the east and Pacific North West. Its rated as “Invasive, banned” in Connecticut and “Prohibited” in Massachusetts. Looks fantastic, but big big trouble: like the kid you saw at the bus stop on the way to school…

At Black Brook Park it was present in acres of vast drifts although in places spring beauty, Claytonia virginica, was holding its own. But it’s plants exactly like claytonia, the early spring ephemerals, that are smothered by the mass of dense early celandine foliage. However, I was also surprised to see a few patches of snowdrops, Galanthus nivalis, looking lush as their foliage stretched after flowering last month.

I could have spent all day examining this huge population of celandines, but a short look indicated that they were very uniform, apart from a few with unusually narrow petals and a few with paler flowers.

In Britain, it’s different. While everywhere at Black Brook Park, New Jersey, the plants had plain green leaves, in Britain the foliage can vary enormously. I picked the leaves in the picture (left, click to enlarge) from a few hundred yards along a quite Sussex lane. The bronze-leaved variety that Christopher Lloyd named ‘Brazen Hussey’ (above, click to enlarge) was found wild in a wood on his property. Other unusual forms, like doubles, also turn up.

But here’s the thing… That sunny carpet of color, disappearing into the distance in that New Jersey park, looked absolutely magical. Is it less beautiful because we know that the plant is not a native?

This week, here in Pennsylvania, the roadsides are bright with a colorful wildflower at its peak. OK, of course, it’s not actually a Pennsylvania native, or even an American native, but it sure looks sunny.

Coltsfoot, Tussilago farfara (above, click to enlarge), is a widespread British plant which presumably came over with colonists. In Britain it grows in many sunny places, often on heavy soils, and it’s been a difficult agricultural weed; its white runners are certainly very resilient.

In the US, it’s now found in much of the east and north east, and in the Pacific North West, while in Pennsylvania the USDA distribution map reveals that our county, Pike County, in the east of PA, is one of the few where it’s not found. Don’t think so: see pictures.

Here in the US, I’ve only ever seen it on roadsides (left, click to enlarge) and in roadside parking areas although the Flora of Pennsylvania reports it “on roadsides, railroad rights-of-way, stream banks, and waste places” – which is pretty much exactly the language used to describe the distribution of Japanese knotweed. The implication being that man’s activities spread it along roads and where road meets river the river takes a hand. In Alabama it’s noted as “Class A noxious weed”; in Connecticut as “Invasive, banned”; in Massachusetts it’s “Prohibited” while in Oregon it’s an “"A" designated weed”. Sounds like it can be a bit of a beast.

But why “coltsfoot”? Well, this more or less describes the hoof-shaped leaves which emerge when the flowers are done. So it’s also been known as horse-hoof, and foal’s foot.

But this is actually quite a useful plant. It turns out – courtesy of Geoffrey Grigson’s wonderful book The Englishman’s Flora – that not only were the dried leaves once smoked to alleviate asthma, but that it’s still an ingredient of herbal tobacco. And, in the long gone days of tinder-boxes, the silver down on the backs of the leaves was collected as tinder. (What a job that must have been.) So perhaps plants were brought to the new world because they were so useful. It seems, in the US at least, they’re now becoming rather the opposite.

But, here in Pennsylvania, I like to see them brightening up the roadsides in spring. Just warming us up for the dandelions - of which more another time.

Just a quickie for St Patrick’s Day on the four-leaf version of the Shamrock. Got to be extra lucky, right?

The Irish Shamrock is usually what the rest of us call white clover, Trifolium repens, or sometimes lesser clover, T. dubium. But there’s at least one variety that always produces four leaves, and sometimes five.

Trifolium repens 'Purpurascens Quadrifolium' – a bit of a mouthful, I know -not only has almost all its leaves with four divisions, there are sometimes five. What’s more, they’re purple with a slender green rim (left, click to enlarge).  It’s very pretty.

But what about that clover in the top of the picture? That’s ‘Green Ice’, one of a number of attractive varieties that turned up by chance in a project designed to develop better varieties for forage.

These are both great foliage plants, but susceptible to attack from weevils which nip the edges of the leaves – and also attack garden peas.

But hey, seems like cheating, doesn’t it, to actually plant a four-leaf clover? Don’t you have to find them by chance for them to be lucky?