Bur Chervil, Anthriscus caucalis

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Bur Chervil, Anthriscus caucalis

Spring Greens: Bur Chervil, Anthriscus caucalis (with Cleavers, Galium aparine) in Limpenhoe churchyard, Norfolk, 25th March 2022.

The hedgerows are starting to brighten up after winter, with Spring flowers – Dandelions, Red Deadnettles, Primroses, Cowslips and many more. These are backed by fresh, bright green growth.

One of the freshest greens on roadsides last week was Bur Chervil, Anthriscus caucalis. It’s a plant that can hide in plain sight, and you’d probably drive past in a car without noticing it. But if you’re cycling or walking, the plant is easy to spot and it’s surprisingly common in many parts of Norfolk.

Anthriscus caucalis is an annual plant and is a close relative of Cow Parsley, Anthriscus sylvestris, which is a more robust biennial or short-lived perennial. It likes light, sandy or gravelly soils and is concentrated in East Anglia, although it has a scattered distribution elsewhere in the British Isles (note 1).

I first noticed large amounts of Bur Chervil in the spring of 2020 when I cycled on the B1113 near Bracon Ash, just outside Norwich. In the last week I’ve noticed it on verges on the hill up to Arminghall and in Limpenhoe churchyard. It favours a south-facing aspect (often at the base of a hedge) and the plant flowers and dies by midsummer, leaving little or no trace until the following spring.

The whole plant is more delicate than Cow Parsley and it grows to about half the height of its commoner relative, to 70cm (about 30 inches) rather than 1.5m (60 inches). Its leaves are fern-like and the flower heads are carried in small clusters (opposite the leaves) in May or June. Its seeds are oval, narrowing towards the beaked tip and are covered in hooked spines. The spines (hairs) can hook to animal fur and woolly clothing and Mike Crewe notes how Bur Chervil is commonly found around rabbit burrows, where the animals have groomed the fruits out of their fur (note 2).

Bur Chervil, Anthriscus caucalis

Bur Chervil, Anthriscus caucalis, in flower at Ringstead Downs, Norfolk, 9th May 2021.

Bur Chervil is sometimes also known as Beaked Parsley and ‘Bur’ can also be spelt ‘Burr’.

Outside the British Isles, Anthriscus caucalis is native in many other European countries, as far east as Ukraine and the north Caucasus, and in the Middle East (Turkey, Syria and Lebanon) and parts of North Africa (Algeria and Morocco).

The plant has spread widely beyond its native range. Perhaps some of the spread has been on sheep’s wool, like Stinking Fleabane (note 3).

Anthriscus caucalis has been introduced to Norway (though it is native to Sweden) and to parts of North and South America, including the United States, Canada, Argentina and Chile. It has recently been introduced to parts of China, CABI’s Invasive Species Compendium lists it as an introduced plant in Kyrgyzstan, South Korea and Australia and Robinne Weiss found it in her garden in New Zealand. (Strangely, Kew’s Plants of the World Online website says it is native to north-east Argentina, a long way from (the rest of) its native range.)

Introduced plants have the potential to become a problem in wild areas and Bur Chervil is pictured in the online Invasive Plant Atlas of the United States (one picture is entitled “Infestation”). There is concern that Bur Chervil can form dense colonies if the conditions are right, but it is not Bur Chervil but Cow Parsley, its close relative, that is listed as a noxious weed in Washington state. A 2018 research paper suggests that Anthriscus caucalis is potentially invasive in Polish forests (note 4).

The Weed Report posted online (from the book “Weed Control in Natural Areas in the Western United States”) recommends control of Bur Chervil by hand-pulling but also lists an array of herbicides that could be used (note 5).

I normally include information on whether a plant is edible or poisonous, but there seems to be surprisingly little data for Bur Chervil, apart from a Chinese paper from 2018 (note 6).

Bur Chervil’s British relatives are certainly edible. Garden Chervil, Anthriscus cerefolium is a well-known and delicious herb (note 1). Cow Parsley, Anthriscus sylvestris, can be eaten too – see my May 2014 blog post and the Eat The Weeds website  for suggestions. But Bur Chervil, who knows? (note 7).

I am going to err on the side of caution, so I don’t plan to eat Bur Chervil any time soon. As well as many edible species, the Carrot family (Apiaceae) contains some very toxic plants, such as Hemlock (Conium maculatum), Fool’s Parsley (Aethusa cynapium) and Hemlock Water Dropwort (Oenanthe crocata). The latter has been described as probably “the most toxic plant in Britain to both humans and animals“ (I wrote about it in November 2018).

Notes

Note 1 – Clive Stace’s “New Flora of the British Isles“ lists three species of Anthriscus. (See page 857; Fourth Edition, 2019.)

The third species is Garden Chervil, Anthriscus cerefolium. This is used as a kitchen herb and can be grown in the garden in light but quite moist soil or in pots outdoors. It adds a delicate, parsley-like flavour (with a hint of aniseed) to dishes and is one of the traditional fines herbes of French cuisine. I’ve grown it on the allotment in semi-shade but it bolts far too quickly in East Anglian spring sunshine and drought.

Note 2 – Mike’s Flora of East Anglia: An Identification Guide website has good photos of But Chervil and other Umbellifers with Rough or Hairy Fruits. Cow Parsley is on the page Long-fruited Umbellifers. As always, I also recommend the Wildflower Finder website for its excellent photographs.

Note 3 – Robinne Weiss thinks “The plant almost certainly arrived in New Zealand on the back of an imported sheep“, thanks to the spines on its seeds.

Note 4 – R. Puchalka, L. Rutkowski, M. Popa, A. Pliszko and M. Piwczynski (2018), “Bur-Chervil Anthriscus caucalis M. Bieb. (Apiaceae) – potentially invasive species in forests“. Baltic Forestry Vol. 24, pp189 – 200.

Bur Chervil was formerly in decline in Poland but seems to have benefitted from human disturbance: “Forest areas in Europe are prone to alien plant invasions, especially when exposed to disturbance, fragmentation, alien propagule pressure and high soil nutrient levels“.

Note 5 – I also found a Farmers Weekly article which lists the herbicides used by some conventional farmers to prevent Bur Chervil becoming a problem in wheat and oil-seed rape fields in the UK . Note to self: buy organic food wherever possible.

Note 6 – P. Lai, H. Rao and Y. Gau (2018), “Chemical Composition, Cytotoxic, Antimicrobial and Antioxidant Activities of Essential oil from Anthriscus caucalis M. Bieb Grown in China”. Records of Natural Products, Vol. 12, pp290 – 294. The essential oil has antioxidant properties but also appears to be cytotoxic.

Note 7 – If you know, please tell me so I can share the information.

Update 31st March 2022: I asked my friend Stephen Barstow (author of “Around The World in 80 Plants : An Edible Perennial Vegetable Adventure For Temperate Climates“) if he had any information on edible uses for Bur Chervil.

He found just a single reference, to the use of Anthriscus caucalis and Anthriscus sylvestris in Azerbaijani cuisine. The leaves and young shoots of both plants are sometimes used in dovga (a soup made from yoghurt and herbs) and qutab (a pattie filled with a variety of ingredients, cooked on a griddle).

Spring Hazelcup, Encoelia furfuracea

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Although autumn is the peak season it is possible to find fungi throughout the year.

Late winter and early spring can be quite productive in mild winters like this one (for those of us in the southern parts of the British Isles at least).  Scarlet / Ruby Elfcups, Sarcoscypha sp. have been fruiting for the last few weeks and it shouldn’t be long before I find my first Alder Goblets of the year.

This January started well when I found my first Spring Hazelcups, Encoelia furfuracea. They were growing in Buckenham Woods, east of Norwich. I hadn’t been there before but it is a lovely place, popular with locals. Most of the site is broadleaved woodland (including an old pit), but there is also an area of grassland and a couple of wetter areas. At the back of the site (to the north-east) there are some Hazels (Corylus avellana) which were coppiced many years ago. They have been allowed to develop complexity and provide a great habitat, with multiple tall stems, mostly alive and healthy, but also some that are dead or dying. It was on the latter I found my Spring Hazelcups.

The Spring Hazelcup, Encoelia furfuracea is a species of Ascomycete fungus (note 1). It is an early coloniser of newly dead or moribund poles of Hazel, where it grows through the surface of dead Hazel bark in clusters or as solitary specimens (note 2).

As well as Hazel, Encoelia furfuracea sometimes grows on Common Alder (Alnus glutinosus) and there is at least one English record on Hornbeam (Carpinus betulus) (note 3).

I was lucky to find Spring Hazelcups in two different stages of growth.

When young the fungi appear as tightly closed brown cups with a scurfy outer surface:

Spring Hazelcup, Encoelia furfuracea

Spring Hazelcups, Encoelia furfuracea. Young specimens: tightly closed brown cups with a scurfy outer surface. Photographed on 10th January 2022.

In older specimens the cups open up to reveal a smooth, dark brown or tan hymenium (spore producing surface), up to 1.5cm across:

Spring Hazelcup, Encoelia furfuracea

Spring Hazelcups, Encoelia furfuracea. Older specimens showing the spore-producing cup surface. Photographed on 10th January 2022.

Having seen my first Spring Hazelcups, I went on to see them in three more places in Norfolk in the next couple of weeks: in deciduous woodland just west of East Carleton, in Foxley Wood (on a Norfolk Fungus Study Group foray) and in woodland close to the railway at Strumpshaw Fen.

After after a week or so of dry sunny weather with some frosty mornings I went back to Buckenham Woods and East Carleton. The specimens I’d photographed had dried up considerably and even the open cups were now partly closed. A bit of rain since then should have revived them, but the strong winds this month have stopped me going to have another look.

Spring Hazelcups are described as “widespread but uncommon” in Sterry and Hughes‘ field guide. There are currently 513 records of Encoelia furfuracea in the NBN Atlas, with records scattered throughout England and much scarcer in Wales and Ireland.

In Scotland Spring Hazelcups grow in Atlantic hazelwoods, such as the wonderful Ballachuan Hazelwood on the island of Seil, south of Oban, which we were lucky enough to visit in May 2018. There are also a cluster of records from Speyside, where Spring Hazelcups have been found on Common Alder (Alnus glutinosus) in at least six different locations.

Encoelia furfuracea can also be found elsewhere in Europe and in North America. The Encyclopedia of Life website lists Andorra, Austria, Denmark, Estonia, Finland, Germany, Italy, Luxembourg, Norway, Poland, Slovenia and Sweden, plus Canada and the United States. I have also managed to find mentions of Encoelia furfuracea in France (a distribution map and photographs), the Netherlands, the Czech Republic and Russia.

Worldwide, there are over 40 species of Encoelia and at least four others have been found in the British Isles (note 4).

If you have Hazels growing near you, take a closer look at them. There is still time this year (note 5).

And if you live in the west of the British Isles, look out for the much rarer Hazel Gloves (Hypocreopsis rhododendri), another fungus that grows on Hazel. Its fawn glove-like fruitbodies are very distinctive and at their best from August to the end of December in Britain and Ireland, though old, blackened fruitbodies persist through much of the year. It’s a species I’d love to see. There are 113 records in the NBN Atlas, sadly none of them remotely near Norfolk.

Notes

Note 1 – Ascomycete fungi produce their spores inside special, elongated cells or sacs, known as asci (singular ascus, from the Greek askós, meaning  sac or wineskin).

Many Ascomycetes (like Scarlet / Ruby Elfcups, Sarcoscypha sp. and Alder Goblets) have cup-shaped fruitbodies, but the phylum is very diverse.

Other Ascomycetes include baker’s and brewers’ yeasts, Ergot (Claviceps purpurea), powdery mildews, Penicillium (the producer of Penicillin) and Scarlet Caterpillarclub.

Note 2 – In Laessoe and Petersen’s two volume ‘Fungi of Temperate Europe‘ Spring Hazelcups are described as erumpent – literally bursting through the surface of the branch. Encoelia furfuracea features on page 1408 in Volume 2, and on page 308 of Sterry and Hughes.

Note 3 – A picture on the Blipfoto website claims to be an old specimen of Spring Hazelcup on Rowan (Sorbus aucuparia) but I’m not convinced.

Note 4 – I haven’t been able to find out much information on the following species. If you know more, please let me know and I’ll add the information.

Note 5 – In Scotland records are mostly between December and May, with single records from June, July and August and then nothing until December. In France, most records are from April.

Stinking Iris, Iris foetidissima

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Stinking Iris, Iris foetidissima

Seeds of Stinking Iris, Iris foetidissima. December 2021.

Flowers are a bit scarce at the moment, though seasonal favourites Snowdrops and Winter Aconites are beginning to make an appearance and Winter Heliotrope has been wowing us with its scent for the past month.

Stinking Iris, Iris foetidissima, is a perennial plant with evergreen foliage. It flowers in late spring and summer (peaking in June and July, though I have seen it flowering in mid May in a sheltered spot on the Isle of Wight). Its flowers are subtly pretty (see the Wildflower Finder website) and attractive to bees but it is the brightly coloured seeds that are the highlight. These last throughout the winter and can be seen at the moment, providing a welcome splash of colour (bright orange or scarlet).

Iris foetidissima is a native of Great Britain, where it is found in hedge banks and in woods, as well as on sheltered scrubby sea-cliffs, with a preference for calcareous soils. It is considered to be an alien in Ireland. Further afield it is native to mainland France, Italy, Portugal and Spain, Morocco, Algeria and Tunisia, the Azores, Balearic islands, Corsica, Sardinia and Sicily. It has been introduced to California, the Canary Islands, Madeira, New Zealand (North Island), Switzerland, Tasmania, Turkey, the former Yugoslavia and possibly Belgium (note 1). The plant can spread vegetatively and by seed. In Britain it is a frequent a garden escape.

There is a lot of Stinking Iris in woodland sloping steeply down to the River Waveney, near Bungay, and this is where I took the photograph above.

Stinking Iris is highly tolerant of drought and shade and will grow beneath trees and even in the darkest dingiest corners. This makes it a good garden plant for difficult places and The Royal Horticultural Society (RHS) have given it an Award of Garden Merit (AGM). Alys Fowler suggests it for “jollying up the base of a leylandii hedge that you can’t get rid of, or for a dark, basement courtyard that only sees a sliver of sunlight“. The BBC Gardeners’ World website has some planting suggestions: “It works well with with other shade lovers such as Euphorbia amygdaloides var. robbiae, and under deciduous trees alongside dwarf spring-flowering bulbs.” It will grow well in sunshine and semi-shade too. Plants are easy to propagate by division and can be grown from seed (sown in late autumn).

The seeds are attractive to birds, especially Blackbirds, which eat them late in the winter. But don’t be tempted to try them. The whole plant – like other irises – is poisonous to humans and contains the toxic isoflavone iridin. Eating small quantities of the plant can cause “extreme discomfort” and symptoms of iridin poisoning in humans include vomiting and bloody diarrhoea and there are records of poisoning in pigs, which died when eating the exposed rhizomes, and in cattle, where some calves died after eating irises in a garden border (note 2).

“Foetidissima” refers to the plant’s unpleasant smell.

If you bruise or tear a Stinking Iris leaf it has a strange smell, described as “roast beef, foetid, or of sweetly acrid meat which is a bit ‘high’” and “rotten raw beef“. I can detect this beefiness. I wouldn’t exactly describe it as ‘Stinking” but it isn’t delightful either, just rather odd. Be a bit careful when handling the plant – the RHS recommends that you “wear gloves and wash hands after handling” and Cooper & Johnson warn that the sap can irritate the skin and even cause blistering (note 2).

Stinking Iris is a member of the Iridaceae (Iris family). It is one of two native species of Iris in the British Isles. The other is the Yellow Flag, Iris pseudacorus, which is better known for its bright yellow flowers. In the Western Isles of Scotland it is a favourite haunt of Corncrakes.

Other names for Iris foetidissima include Scarlet-berry Iris, Gladdon, Gladwin Iris, Roast-beef Plant, and Stinking Gladwin. “Gladdon” and “gladwin” refer to the sword-like leaves (from the Latin ‘gladius‘, note 3).

There are a few cultivars of Iris foetidissima that are worth looking out for. Alys Fowler mentions a golden-seeded variant which sounds lovely (‘Golden Seeded’ or ‘Golden Gobbet’) and there is also ‘FructuAlbo’, whose seeds are “polished white ones that sit inside the furry interior of the seed head like brilliant pearls“. Unusual leaf forms include striped (‘Variegata’) and yellow (‘Paul’s Gold’) . There is also a dwarf form.

Stinking Iris flowers are normally a mix of dull shades of mauve, blue, yellow and white.

Stinking Iris, Iris foetidissima

Iris foetidissima – typical form. Topcroft churchyard, Norfolk.

Alys Fowler mentions a form with yellow flowers, ‘Citrina’. I think this is what I saw on the Isle of Wight in May 2019 and, more recently, at New Buckenham church in Norfolk.

Stinking Iris, Iris foetidissima

Stinking Iris, Iris foetidissima – form ‘Citrina’, I think. New Buckenham churchyard, Norfolk.

Notes

Note 1 – Stinking Iris was first recorded in Belgium as recently as 2008. The plant is thought to have escaped from cultivation, but the Manual of the Alien Plants of Belgium website says that “a natural range extension [from northern France], cannot be ruled out”.

Note 2 – M. R. Cooper and A. W. Johnson (1988): “Poisonous Plants & Fungi – An illustrated guide”, HMSO, London.

The chemical that causes blistering is Irisquinone. It closely related to Primin, the substance that causes contact dermatitis in some species of Primula.

Note 3 – As in ‘gladiator‘. Another plant in the Iris family (Iridaceae) is Gladiolus, which means “little sword”, again from the shape of the leaves.