Five Fungi from the Streets of Norwich

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I live in the south-western suburbs of Norwich and I’m very fortunate to have plenty of tree-lined streets with grass verges near home. As a consequence, I often find interesting fungi on my walks, sometimes just on a trip to the local shops.

Here are five recent finds.

Ganoderma resinaceum

Last summer some large objects appeared on a grass verge not far from home. With a few added toppings they could easily have been family-sized thick-crust pizzas.

Ganoderma resinaceum

Ganoderma resinaceum

The objects were fruitbodies of a large bracket fungus, Ganoderma resinaceum, which is parasitic on broadleaved trees, especially oaks and Beech. The fungus was growing on the remains of a Red Oak (Quercus rubra) that had toppled over in a gale several years ago. It had presumably started to eat the tree while it was alive and then continued to digest its remains.

Like its close relatives Southern Bracket (Ganoderma adspersum), Artist’s Bracket (Ganoderma applanatum) and Lacquered Bracket (Ganoderma lucidum) it can grow at the base of tree trunks. However, I’ve only seen it growing on the ground, feeding on the remains of tree roots.

I found another Ganoderma resinaceum this summer on a verge south-west of Norwich, growing on another subterranean oak root. Over the weeks I watched it grow in size from small bread roll to medium loaf but it didn’t reach pizza size, presumably because it had a more limited food supply. Similarly, my local specimens were much smaller this summer, suggesting that the remnants of the Red Oak are dwindling.

Ganoderma resinaceum

Ganoderma resinaceum

Although Ganoderma resinaceum can resemble a pizza, the resemblance ends there. The fungus has a spicy smell but apparently tastes bitter and is far too tough to be edible.

Ganoderma comes from the Greek words Ganos and derma and means ‘shining skin’. (The wet cap of Lacquered Bracket, Ganoderma lucidum, is the finest example of this.)

The specific name resinaceum means ‘resinous’. The fungus has a hard resinous coating which will melt when set alight. I haven’t tried this yet; next year, perhaps.

Mealy Domecap, Tricholomella constricta

Mealy Domecap, Tricholomella constricta

Tricholomella constricta – Mealy Domecap. Photo: Vanna Bartlett.

Last October, while walking home from the shops, I found some bright white fungi growing on a road verge. They completely puzzled me but Yvonne from the Norfolk Fungus Study Group came to the rescue and identified them as Mealy Domecap, Tricholomella contricta.

The species has also been seen at Whitlingham Lane in Norwich and in the grounds of the University of East Anglia. It appears to favour road verges where dogs urinate (note 1). Knowing this, James Emerson searched likely places in the north of Norwich and soon found the fungus in a spot in New Catton.

Now that I’m familiar with this fungus, it’s easy to recognise. It has a bright white cap, white notched-adnexed gills and a rooting, tapered white stem with a small ring. The fruitbodies smell farinaceous (floury) and are quite robust. Each one can last for a week or two, even in rainy weather.

Vanna found me some more specimens this year, growing on another grass verge in Norwich, in a spot popular with dog walkers.

Tricholomella constricta

Tricholomella constricta

Andy Overall found the fungus growing in Holland Park in London in 2011 (note 1).

Ascot Hat, Hortiboletus bubalinus

Ascot Hat, Hortiboletus bubalinus

Ascot Hat, Hortiboletus bubalinus

At the time of writing the Ascot Hat, Hortiboletus bubalinus, has only been seen in Norfolk four times, all in Norwich. Last autumn James Emerson found the first one not far from the city centre, followed a month later by a second sighting made at the University of East Anglia by Ian Senior.

This year I’ve followed up with the third and fourth sightings, from a road verge under Common Limes, and under pine trees in my local cemetery.

Hortiboletus bubalinus is a handsome fungus but is very easy to miss when growing on a grass verge, where its cap (in various shades of pinkish-, yellowish- or reddish-brown or dull apricot) blends into the background.

But if you take a closer look it is an exquisite fungus. Its pores bruise blue when handled, like several other species of bolete and if you cut it open the cap is reddish-brown on top with a pink layer, before staining light blue further down. The colour scheme has been described as being like “sunrise over the sea” (note 2).

Hortiboletus bubalinus

“Sunrise over the sea”. Cut open: Hortiboletus bubalinus

Hortiboletus bubalinus was only described in 1991. It was originally known as Boletus bubalinus and became Xerocomus bubalinus in 1993. It was transferred to Hortiboletus in 2015. It appears to be quite new in Britain and was first recorded near Ascot. The Guardian asked for suggestions for an English name back in June 2011 and the English name is now Ascot Hat, which makes more sense when you know about its origin in Britain.

Ganoderma resinaceum is a parasite and Mealy Domecap is presumably a saprobe (eating dead organic matter). Ascot Hat has a symbiotic relationship with trees, helping them take up water and minerals in exchange for carbon from the tree.

It appears to form mycorrhizal relationships with a range of trees, including limes (Tilia), poplars (Populus), Beech (Fagus), birch (Betula), spruce (Picea) and Hornbeam (Carpinus). One of my specimens was growing with Common Lime (Tilia x europaea) and  the other near Scots Pine (Pinus sylvestris).

Hortiboletus bubalinus is edible but I haven’t tried it and probably won’t, given its apparent scarcity in Norfolk. I returned my specimens so that they could continue to release their spores.

Warty Cavalier, Melanoleuca verrucipes

Warty Cavalier, Melanoleuca verrucipes

Warty Cavalier, Melanoleuca verrucipes

At the beginning of October I found Warty Cavaliers (Melanoleuca verrucipes) in woodland at the end of my local park. At first I thought the dark marks on the stems was just where soil had splashed upwards in the rain. I took one home to identify.

This was just the fourth record for Norfolk. Warty Cavaliers like to grow on woodchip and this had been spread along the path through the wood, spilling off into the woodland where the fungi were growing. Melanoleuca verrucipes is a saprobe and its favourite meal is wood chip mulch. It was first recorded in Britain in 2000 and is probably an introduction (note 3).

The genus name Melanoleuca comes from the Ancient Greek melas (black) and leucos (white) and other fungi in this genus (Cavaliers in English) have a dark top to the cap and contrasting white gills. Warty Cavalier looks rather different, making it quite easy to identify once you know where to look. Verrucipes means ‘with warty foot’ and refers to the stem.

Under the microscope, Melanoleuca verrucipes has rather nice urticoid cheilocystidia. I explain more in note 4 below.

Warty Knight, Melanoleuca verrucipes - urticoid cheilocystidia

Warty Cavalier, Melanoleuca verrucipes – its urticoid cheilocystidia.

The Warty Knight may be edible but is likely to be “nothing special“. I wouldn’t bother.

The First Nature website has more photographs of Warty Cavalier, including the spores.

Blushing Rosette, Abortiporus biennis

My fifth fungus is Blushing Rosette, Abortiporus biennis.

I was very puzzled when I first saw this fungus, growing on the underground remains of another tree (possibly another Red Oak). It looked like it might turn into a bracket of some kind, but which species?

I posted a photograph on the Norfolk Fungus Study Group Facebook page and Neil Mahler came up with an identification: Blushing Rosette, Abortiporus biennis.

Blushing Rosette, Abortiporus biennis

Blushing Rosette, Abortiporus biennis. 11th October 2023.

Rosette, what rosette?

I made a return visit at the end of the month and it was very much in evidence.

Blushing Rosette, Abortiporus biennis

Twenty days later: Blushing Rosette, Abortiporus biennis. 31st October 2023.

But the prize for the wackiest specimen of Blushing Rosette must go to a huge outpouring of growth on a fallen tree trunk in Earlham Park in Norwich, which Vanna found earlier this month. It resembles a series of volcanic cones rather than a fungus.

Blushing Rosette, Abortiporus biennis

Blushing Rosette, Abortiporus biennis. Earlham Park, Norwich, November 2023.

Abortiporus biennis is another saprobic fungus, feeding on the dead remains of broadleaf tree roots and stumps.

If you look at the underside of the rosette you will see a network of white or buff angular pores.

The genus name, Abortiporus, comes from the Latin Abortus– meaning arrested development (of an organism), and –porus, derived from ancient Greek and meaning a pore. The specific name biennis is misleading. Biennis means biennial but the fruitbodies are annual. The fungus isn’t edible and you might break your teeth if you tried to eat it.

The First Nature website has more photographs of Blushing Rosette, including the spores.

Notes

Note 1 – One Norfolk record was from a cat latrine and another specimen was growing in Earlham Cemetery, possibly on an animal latrine (although some people insist on ignoring the “No Dogs” signs).

In his article “Urban Fungi – interesting fungi from parks and gardens of West London” (Field Mycology Vol. 14 pp98 – 102, 2011) Andy Overall notes “This species is known to favour urine-enriched sites …more probably the common factor is merely the presence of dogs.”

Note 2 – A post on Reddit by “the frisker” mentions the “Sunrise over the sea” nickname and gives “Aurora Bolete” as a Scandinavian name for Hortiboletus bubalinus. “Sunrise above the sea” is mentioned in “Fungi of Temperate Europe” (page 786) by Thomas Læssøe and Jens H Petersen (Princeton University Press, 2019).

Note 3 – Geoffrey Kibby (2020), “Mushrooms and Toadstools of Britain & Europe – Volume 2, Agarics – part 1”. (One of four superb volumes for identifying British Basidiomycete fungi.)

Note 4 – Cystidia are relatively large cells found in various places on the fruitbody of a Basidiomycete fungus. They vary in shape between species and this can be key to the microscopic identification of fungi.

Cheilocystidia are cells that project from the edge of the gill of a fungus fruitbody. “Urticoid” means shaped like a stinging-nettle hair (with a long straight pointed section and a swollen base).

Japanese Honeysuckle, Lonicera japonica

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Japanese Honeysuckle, Lonicera japonica

Japanese Honeysuckle, Lonicera japonica.

Beautiful Flowers with a Scent of Vanilla

Our Japanese Honeysuckle, Lonicera japonica, is flowering profusely at the moment. It started flowering in June and will continue to do so until we have our first severe frost. It’s a cheery sight. The flowers smell of vanilla (especially on a warm evening) and in the warmth of early October it attracted early autumn visitors to the garden, such as queen Buff-tailed Bumblebees (Bombus terrestris) and a fleeting Hummingbird Hawkmoth (Macroglossum stellatarum).

When we moved here, just over ten years ago, the Japanese Honeysuckle was the only plant of any significant size in the garden, which was otherwise covered in lawn, slabs and gravel. It hides – and keeps together – a wooden trellis that divides the garden in two.

We are very lucky to have House Sparrows (Passer domesticus) in our garden. They love the dense tangle of our Japanese Honeysuckle and spend a lot of time there, darting out to the bird feeders and nesting in nearby eaves.

Lonicera japonica is a member of the family Caprifoliaceae (note 1). It’s a climbing shrub which is partially winter-green, only losing its leaves in colder winters. It is widely grown in gardens, usually as Lonicera japonica var. halliana, known as ‘Haliana’ in the UK and ‘Hall’s Prolific’ in the United States.

Native to Eastern Asia

Lonicera japonica is a native of eastern Asia, including Japan, Korea, Taiwan and many parts of China. It has been introduced to many other parts of the world, including the British Isles and other parts of Europe, other parts of Asia, North and South America, parts of Africa, Tasmania and North Island in New Zealand. It is easy to understand why: it makes a useful and lovely screen.

Japanese Honeysuckle is also known as Gold-and-silver Honeysuckle because of its flowers, which start off white and age to a golden yellow. The flowers are followed by berries, which ripen to black.

Japanese Honeysuckle, Lonicera japonica

Japanese Honeysuckle, Lonicera japonica. The flowers start off white and age to a golden yellow.

Widely Introduced

Lonicera japonica was introduced into Britain in 1806. It can now be found growing in the wild in the British Isles, in woodland margins, scrub, hedgerows and on waste ground. Most records are from England and Wales, with some more in the south of Ireland, with outliers in Western Scotland and Northern Ireland.

Japanese Honeysuckle can spread very successfully. Birds and other animals eat the berries and can disperse the seeds in their droppings. The plant spreads vegetatively too and I have noticed in our own garden how the long twining stems travel across the ground and root where they meet the soil. Sometimes humans provide assistance – some of the wild Japanese Honeysuckle plants are garden throw outs.

Colonies of Japanese Honeysuckle can be long lived, such as at Bere Ferrers in South Devon where the plant has been known since 1937. In North Norfolk, a large colony of the Japanese Honeysuckle has become established on the coastal defence bank at Cley-next-the-Sea. The BSBI Plant Atlas notes that the plant’s range appears to be increasing here.

Sometimes Invasive

Elsewhere, Japanese Honeysuckle can be far too successful. In New Zealand it is listed in the National Pest Plant Accord as an unwanted organism and in North America it is classified as a noxious weed in Texas, Illinois, and Virginia and is banned in Indiana and New Hampshire. The plant spreads most successfully into forests when the canopy has been opened up, such as by felling.

Ireland’s National Biodiversity Data Centre website cites several studies on the detrimental effects of Lonicera japonica in the United States, including a decline in native species in areas it has colonised. The plant is thought to inhibit the growth of competitors by means of allelochemicals (chemicals that prevent the growth of other plants) and thrives because it lacks specialist herbivores.

Where they are growing in the wrong place, small patches of Japanese Honeysuckle can be removed by hand or dug out, but all plant parts including roots and rhizomes must be removed to prevent resprouting. Larger patches are removed through repeated mowing or by the use of herbicides. There is currently no known biological control. The Invasive Plant Atlas of the United States and University of Florida Center For Aquatic and Invasive Plants websites provide useful information; the latter has more details on control of Lonicera japonica in the United States. It also lists some American natives that can be grown instead (note 2).

Uses For Food and Medicine

The Plants For A Future website notes that the flowers and leaves of Lonicera japonica are edible but the leaves contain saponins and must be cooked thoroughly first. I haven’t bothered to eat either of them, though we once made an acceptable wine from the flowers of Lonicera periclymenum (Common Honeysuckle) growing in our previous garden. Wikipedia gives details of Japanese Honeysuckle’s uses in Chinese medicine.

Worth Growing in the British Isles

In the British Isles I wouldn’t hesitate to grow Japanese Honeysuckle in my garden. The RHS website gives details of Lonicera japonica ‘Halliana’ and how to grow it. Our plant thrives on well drained soil in a sunny spot. Lonicera japonica is hardy to -10 to -15C (UK hardiness rating H5).

In our garden it grows to about 2.5 metres (8 feet) tall and spreads about double that distance along the trellis. I prune the top shoots once or twice in the summer and remove wayward, rooting branches – though if you want a free plant to give away these can be dug up and planted elsewhere. If you want to buy a Lonicera japonica, a Google search gives plenty of online stockists and your local garden centre probably has it too.

Notes

Note 1 – I wrote about its relative, the shrubby, winter-flowering Lonicera × purpusii ‘Winter Beauty’, in March 2015. It is one of the species and hybrids of Lonicera listed in Clive Stace’s “New Flora of the British Isles“ (Fourth Edition, 2019). Just one of these, Lonicera periclymenum (Common Honeysuckle), is a British native. It also occurs in many garden varieties. See Mike Crewe’s Flora of East Anglia for comparative photographs of the species of Lonicera that occur in our part of the British Isles.

Note 2 – Ironically one of these is Virginia creeper (Parthenocissus quinquefolia), which can be a real thug in our garden, where it spreads from behind our fence into the shrubs at the end of our garden.

Tall Willowherb, Epilobium brachycarpum

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No one could describe Norwich’s Northern Distributor Road (NDR) as pretty but recently Tall Willowherb, Epilobium brachycarpum, has been brightening up the central reservation between Norwich Airport and the A140 Cromer Road. As I cycled north from Norwich in early September, crossing the dual carriageway with the help of a pedestrian refuge, I stopped to take some photos of the plant.

Tall Willowherb, Epilobium brachycarpum

Tall Willowherb, Epilobium brachycarpum, by Norwich’s Northern Distributor Road. 6th September 2023.

Tall Willowherb, Epilobium brachycarpum, has pink flowers but by the time of my visit in early September the plant was mostly a reddish haze of stems and seed pods.

Tall Willowherb is a thin, gangly annual plant which normally grows up to one metre (39 inches) tall, though it can occasionally reach twice this height. Its leaves are narrow, curving and pointed. The pink flower petals have darker pink veins. There are four petals per flower but they are so deeply notched they almost look like eight. The red fruit capsule is 1 to 3 centimetres (0.4 – 1.8 inches) long.

Tall Willowherb, Epilobium brachycarpum

Tall Willowherb, Epilobium brachycarpum. Detail of flower and fruit capsule.

Epilobium brachycarpum, is also known as Panicled Willowherb, Tall Annual Willowherb and Tall Fireweed. It is a member of the family Onagraceae, like Great Willowherb, which I wrote about in August 2022.

Tall Willowherb was first recorded by the NDR in 2019. It is a native of North America, where it grows in varied open and woodland habitats in Canada and the northern and western United States and parts of Mexico. It has been introduced into Wisconsin and Kentucky, Argentina in South America and parts of Europe (Belgium, Czech Republic and Slovakia, France, Germany, Great Britain, Netherlands and Spain).

A Recent Arrival

Epilobium brachycarpum is a recent arrival in the British Isles and was first found in 2004 in gravel workings near Colchester in Essex. It has since been found in Kent, Surrey and Norfolk (note 1). The BSBI Plant Atlas describes its habitat in the British Isles as “open ground on nutrient-poor sandy and gravelly substrates, including quarries, railway sidings and other brownfield sites“.

North American Tall Willowherb plants have 4-lobed stigmas and are usually out-crossing but British plants have clavate stigmas and appear to self-pollinate.

Tall Willowherb produces masses of viable seed, enabling it to spread very rapidly. The BSBI Plant Atlas predicts that the plant “is highly likely to spread further over the coming decades“, so keep a look out for it.

Identifying willowherbs can be very difficult but Mike Crewe’s Flora of East Anglia website has useful photographs of willowherbs for comparison (he uses the name “Tall Annual Willowherb” for Epilobium brachycarpum). Epilobium brachycarpum is “a very different plant to any of our native species“. The gallery tab on the BSBI Plant Atlas website has plenty of good photographs of the plant, as has the Burke Herbarium website (University of Washington).

Bob Leaney’s article (note 2) provides a lot of help if you want to identify willowherbs. Luckily Epilobium brachycarpum is “easily recognised by its panicled flowers with tiny, deeply bifid petals, minute linear leaves, short, slightly curved fruits and exceptionally fine, wiry stems“.

Tall Willowherb, Epilobium brachycarpum

Looking west: Tall Willowherb, Epilobium brachycarpum, by Norwich’s Northern Distributor Road. 6th September 2023.

Multiple Introductions

Epilobium brachycarpum was first found in Europe in 1978. A 2016 study looked at populations of Epilobium brachycarpum in Germany and northern France and found that the plant had been introduced into Europe more than once. More invasive Tall Willowherb plants came from high mountain areas in North America and a less invasive and smaller German population came from lowland areas but suffered from frost damage, making its permanent establishment doubtful (note 3).

Notes

Note 1 – This was the second time I’d seen Tall Willowherb in my local area. My previous encounter was on the edge of a pavement by a building site in King Street in Norwich in June 2022.

Thanks to Chris Lansdell for telling me about the King Street plants. They had been spotted by champion plant hunter Louis Parkerson, who also found the Stinking Fleabane that I wrote about in October 2021.

Note 2 – Bob Leaney (2020), “Common problems with identification in Epilobium (willowherbs)”. BSBI News Vol. 144, pp5 – 13.

Note 3 – K. Nierbauer, J. Paule and G. Zizka (2016), “Invasive tall annual willowherb (Epilobium brachycarpum C. Presl) in Central Europe originates from high mountain areas of western North America”. Biological Invasions Vol. 18. Available as a PDF at https://www.researchgate.net/publication/304917418_Invasive_tall_annual_willowherb_Epilobium_brachycarpum_C_Presl_in_Central_Europe_originates_from_high_mountain_areas_of_western_North_America.