Hyde park Poplar
It was love at first sight; one of those eyes across the Park moments. Standing as sentinel in an open wooded habitat amongst scarlet Pin Oak and yellowing Salix, this tall dark stranger had a monumental Gothic presence. High up in the canopy, triangular whispering leaves were hanging on to their lime-green vestments well on into late November. Aside from a mossy North face,1 the bark was intensely grey-black and most alluringly tactile. It was not hard to imagine a volcanic crater secreted in the crown, whereby larva had oxidised down in overlapping, butted verticals.
Dark furrowed trunk
Given the bark’s colouration, I had first assumed it to be one of the UK’s rarer native Black Poplars but after a deal of research, finally nailed it down as Populus x canadensis (I think correctly although identification of Poplars requires a somewhat specialist knowledge!). Hybridised in the 18th Century from Black poplar (Populus nigra) and the American Eastern Cottonwood (Populus deltoides), the Black Italian Poplar is quite significantly taller than its Populus nigra parent. Having a more compact crown of upward growing branches, the strongest identification comes from the long deeply furrowed trunk, devoid of the tell-tale knobbly bolls or bosses. The popularity of this faster growing tree increased in the 19th Century where its poorer quality timber was appropriated for the more utilitarian production of matches, crates, clogs and flooring.
Exit Holes on Poplar
Being such an impressively healthy specimen of Poplar, I was surprised to see a tumorous outgrowth where trunk and root met in the grass line. Closer inspection of the deformity revealed woodworm-type bore holes which made me wonder if the tree was rotting from the base up. A quick google of wood borers on Poplar however revealed that in fact these were most likely to be the exit holes of a rather scarce and unusual UK insect: Sesia apiformis or Hornet moth.
In striking vespa colouration, this British clearwing moth lives and loves in around Poplar trees. Eggs are laid at the trunk base where the hatched larva feed by boring into the bark and eventually cocooning themselves in the tunnels. Taking between 1-2 years to reach maturity, the adults are on the wing in summer, with a jagged flight pattern that completes their hornet mimicry. They may be spotted at rest low down on the trunks in early to mid morning but are rarely seen north of the Midlands.
Sesia apiformis images from Wikipedia
Hornet moths on Poplar
Evidence from the timber industry pinpoints Sesia apiformis as a significant pest of Poplar but there is a difference between the goals of commerce and arboreal ecology. A summary review of decade old studies by Eureka Mag indicates that human activity and climatic variations may be at the root of the Populus dieback problem:
“the moth most likely acts as a secondary agent in tree decline. Up to 53 per cent of trees with severe dieback occurred in shelterbelts, and many of these sites were situated on reclaimed land or other man-made substrates. The area where dieback has been most prevalent is one of the hottest and driest parts of the UK, and the reports of dieback in Poplar and the apparent increase in S apiformis activity, follow particular dry springs and early summers.” 2
Poplar Tree Dryad
Poplars are often associated with river banks although many eke out an existence in non riparian zones, including industrial cities (e.g. the Manchester Poplar hybrid). This Black Italian Poplar is thriving in it’s Hyde Park setting perhaps because it is protected by the little gnarled tree Dryad which has formed from the activity of the Poplar loving Hornet moth. I shall revisit in Spring and Summer for an update.
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Postscript: For my own edification, I aim to do a collection of Tree ID posts, in and around London. Next time: The Black Poplar – much nearer home than I would have expected….
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Notes:
1. Moss and lichen growth on tree trunks indicate a northern direction – a helpful bushcraft tip if ever you are lost in the woods. On this tree the bat box has thus been placed to the east – not the best locale given that Bats need the warmth of a south facing shelter.
2. Eureka Mag: Sesia Apiformis
Further Reading:
Poplar Trees
Identifying ClearwingsUK Moths
And finally… A delightful video of the Clearwing Moth mating ritual – a rather long and haphazard love affair set in the slightly artificial setting of a Butterfly farm but the shots are magnificent.
Hi Laura
I have a fascination with lichen and I am always on the look out for new additions to my photographic collection. Alas I don’t have the same attraction to those dreadful hornets. Since this one is called a moth does it have a sting?
Truly a post written by someone in love.And I so enjoyed it and look forward to a series of tree posts. There is a small collection of white poplars not far from here-with amazing eye-like patterns on their trunks.I am hoping you will do a feature post on them after the Black poplar, if you know where there is one growing.
Dear Laura, A majestic tree indeed. I was most fascinated to read your information about the tree as it was certainly quite new to me. The London parks do contain the most wonderful trees, many of which have now grown to maturity and are spectacular.
- Dear Rosie, mosses and lichens must thrive in your Northern hemisphere. And no fear, the moth is absolutely stingless
- Dear Judith, so glad you enjoyed this post and will definitely add White Poplars to the list – once I’ve located one!
- Dear Edith, Took a while to gather this info as my love for trees is far greater than my knowledge. Indeed. How barren London would be without our woodland parks and street trees
I love poplars. In Maine, US, we have the magical quaking aspen whose Latin name Populus tremuloides says it all. I am excited that I am going to learn about London’s trees. Carolyn
Dear Carolyn , When I think of Aspens, I think Autumn. Now that’s a challenge – wonder if I can find one of those here!
Laura
p.s. my sister lives in Maine
This is my kind of tree! I want to run my hands over that magnificent bark. Thanks for an informative post.
I share your love of trees Laura. Fantastic hornets! All presented with the wonderful use of the English language which the lovely Edith Hope also uses beautifully.
- Dear Deb, my feelings exactly -the bark is a work of art.
- Welcome Alistair, thanks for the visit and your kind words. It’s been refreshing to read bloggers like Edith who can write so well
Laura, I enjoyed the information in your post. Poplars here support the Viceroy butterfly. They do no damage to the tree like your borers. I am going to file your post because it was so informative and well written.
Dear Donna – thank you! Blushingly chuffed
Poplars popular with much wildlife – the bark alone is shelter for myriad insect life
A true love story … what a fantastic read! I don’t think I’ll ever look at a majestic-looking tree in the same way ever again! You do have such a wonderful way with words … another enjoyable informative post!
[...] of poplars. I had read a very interesting post about Black poplars (Populus nigra ssp. betulifolia) here and had my eyes open for them. The ones in this picture are almost certainly Lombardy poplars, of [...]
thank you Judith for the post link. Beautiful descrption of your winter walk with the trees which inspired your lovely watercolour of Oak with distant Poplars
Settling into Winter.
I’m glad that such an amazing old tree has its own dryad. It would be very sad if nothing mythical had taken advantage of such prime real-estate.
- Dear Bernie, thank you for the very nice compliment and for always stopping by with encouraging words
- Welcome Eliza, Thanks for visiting. I rather liked the Poplar’s Dryad – complete with leaf in cap.
Dear Laura, I really respect the amount of research that went into this posting as, like you, my love for trees far outweighs my knowledge of them. I just found a new love – the European Copper Beech and wish I had taken some close-up pictures of it. Look forward to more in your tree series. P. x
Dear Pam
thanks for the recognition of the research efforts. The copper beech is indeed another tree that inspires love
see here
Very nice tree, and interesting fact about the Hornet
Hi Laura…an excellent article….really enjoyed reading it..
The moth is remarkably Hornet like in its colouring – very good protection. I have never seen one before.
- thank you Fer and Mike, hope you enjoyed reading as much as I enjoyed writing
- EG, have never seen this remarkable moth so will return in summer to see if I can spot it