Devil’s-bit Scabious, Succisa pratensis

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Devil's-bit Scabious, Succisa pratensis

Devil’s-bit Scabious, Succisa pratensis, at Buxton Heath, late August 2020.

We are now at summer’s end. Days are noticeably shorter and there are fewer flowers and insects, but there are still many things to look at and enjoy. Not least are late flowering plants such as Ivy (and its attendant insects), Grass of Parnassus and Devil’s-bit Scabious.

Devil’s-bit Scabious, Succisa pratensis, is flowering at the moment in Norfolk, and attracting plenty of hoverflies, butterflies and bees.

It is a perennial plant which has a basal rosette of leaves. From July onwards the plants send up nodding stems up to one metre (40 inches) tall, topped with flower heads, a tight bunch of buds (described as like boxing gloves) which open out into lilac-blue pincushions.

Succisa pratensis in bud

Succisa pratensis in bud: “like boxing gloves“.

Succisa pratensis

Succisa pratensis – open flower, like a pincushion.
Many more photos can be found on the Wildflower Finder website.

Devil’s-bit Scabious is one of three native species of scabious in the British Isles, the others being Small Scabious, Scabiosa columbaria, and Field Scabious, Knautia arvensis. Along with Teazels (Dipsacus sp.), these plants form a natural grouping: family Dipsacaceae (the Teasel family), or subfamily Dipsacoideae, part of the Caprifoliaceae (Honeysuckle family) (note 1).

Small Scabious grows in dry, calcareous grassland and in rocky places such as cliff tops, and Field Scabious grows in dry, grassy places on light soils. In contrast, Devil’s-bit Scabious is found in a wide variety of grassy places, including woodland rides, heathland and grassland and in mires, and in the uplands on cliff ledges and in ravines.

In Norfolk, Devil’s-bit Scabious grows in very different places: in valley mires and fens such as at Upton Fen and Buxton Heath, but also on the dry chalk ramparts of an Iron Age fort at Warham Camp. These areas have one thing in common:  more dominant species of plant are being held in check either because the soil is not particularly fertile, or because of grazing pressure.

Succisa pratensis is found throughout the British Isles in suitable areas where the grassland has not been “improved” (note 2), but it has had a widespread decline in southern and eastern England since 1950.

Scabious plants were used to treat skin conditions such as scabies (a contagious skin infestation caused by the mite Sarcoptes scabiei, note 3), and even bubonic plague. Devil’s-bit Scabious is still used in the treatment of eczema and other skin conditions. Other medicinal uses listed on the Plants for a Future website include the treatment of coughs, fevers and internal inflammations, and externally to treat bruises or conjunctivitis. Young shoots are edible and sometimes used in spring salads.

It is illegal to dig up plants without the landowner’s permission (note 4) and I don’t recommend it for Devil’s-bit Scabious, but if you did you would find that the root is black and rather short. The suggested reason was that the Devil bit the bottom of the root off, because he was angry at the plant’s medicinal qualities.

As well as being a great source of nectar for insects, Devil’s-bit Scabious is the foodplant of the Marsh Fritillary, Euphydryas aurinia. The butterfly is mainly found in the western half of Britain, having suffered a dramatic decline since the 1970s. I first saw one in The Burren in Ireland in 1985, with my next sightings over thirty years later, near Oban in Scotland (2018) and in the Lake District (2019), where the butterfly has been reintroduced.

Marsh Fritillary

Marsh Fritillary, Euphydryas aurinia.

We grow Small Scabious and Field Scabious in our garden. The former is in a gravel garden (now much wilder than when I wrote about it in 2013) and the latter in our wildflower meadow. Both do well in my dry, sandy loam. I haven’t tried growing Devil’s-bit Scabious but it would make a lovely addition to a garden, is very hardy and will flower for a long period.

The RHS website says that Succisa pratensis will grow in any moist soil in sun or partial shade and is excellent for peaty bog garden. Given that it grows wild in well drained conditions at Warham Camp, it might be worth experimenting if your soil is drier. Pot-grown plants are available online (for example, from Claire Austin and Sarah Raven), or you can buy seed (Emorsgate Seeds). Seed is best sown in the autumn: I might even give it a try.

Notes

Note 1 – Clive Stace considers the Dipsaceae to be a family, in his “New Flora of the British Isles“. (Fourth Edition, 2019.)

Note 2 – See Note 3 in my post about Green-winged Orchids.

‘pratensis‘ means ‘growing in meadows‘.

Note 3 – In Latin, scabere means to scratch.

The subspecies of mite Sarcoptes scabiei canis can infest dogs, cats, foxes, pigs, horses and sheep, causing sarcoptic mange.

The condition is very unpleasant in foxes and will lead to the death of an infected fox if it is not treated. It is probably the reason why fox numbers in our part of Norwich have crashed in recent years. (We no longer have foxes next door.)

The National Fox Welfare Society offers free mange treatment.

Note 4 – The Wildlife and Countryside Act (1981) makes it illegal “to uproot any wild plant without permission from the landowner or occupier” in Britain. See the Plantlife website for more information.

Yellow Loosestrife, Lysimachia vulgaris

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Yellow Loosestrife, Lysimachia vulgaris

Yellow Loosestrife, Lysimachia vulgaris, at Redgrave and Lopham Fen.

In mid July our friend Sarah drove us to Redgrave and Lopham Fen, rightly described as “the largest valley fen in England and one of the most important wetlands in Europe.” It is a Suffolk Wildlife Trust reserve, straddling the upper reaches of the River Waveney, which forms the border between Norfolk and Suffolk (note 1).

Yellow Loosestrife, Lysimachia vulgaris, was just coming into flower, forming patches of bright yellow amongst the reeds, in contrast to the pale lilac flowers of Creeping Thistles, Cirsium arvense, growing beside the path.

Yellow Loosestrife (or Yellow-loosestrife) is a characteristic perennial plant of river banks,  stream sides, marshes, fens and the edges of ponds and ditches. It is widespread in lowland Britain and Ireland where these conditions occur. It can be lost if wet places are drained or ditches are cleared but it can also colonise suitable new sites, possibly assisted by waterfowl (note 2). It grows to 1.5 metres (five feet) tall, with branching stems topped with clusters of attractive yellow flowers. Outside the British Isles, Lysimachia vulgaris is a native in many European countries, westwards into Asia and in Algeria in North Africa. It has been introduced into parts of North America and parts of New Zealand.

Along with the Cowslip (Primula veris) and Primrose (Primula vulgaris), which I’ve already written about, Yellow Loosestrife is a member of the Primulaceae, the Primrose family.  Stace’s Flora lists eleven species of Lysimachia in the British Isles (note 3). Lysimachia is named after Lysimachus, a king of Sicily, who is said to have fed a member of the genus to an angry bull to pacify it (note 4). Vulgaris means common. The English name “loosestrife” is shared with another waterside plant, Purple Loosestrife, Lythrum salicaria (family Lythraceae), but this isn’t a close relative (note 5).

Cowslips and Primroses flower in spring, but Yellow Loosestrife flowers much later, in July and August. (See The Wildflower Finder and First Nature websites for some excellent photographs of the plant in full flower.)

The genus Lysimachia is interesting because around 40% of the species, including Lysimachia vulgaris, have evolved to produce floral oils, rather than nectar, as a reward for visiting bees (note 6).

Floral oils are mostly made up of long-chain acetoxy-substituted free fatty acids and have the consistency of olive oil. They are secreted by special thin-walled glands on the stamen tubes and the inner, lower surface of the petals, known as trichome elaiophores. Floral oils are often scented: in a 2007 study by Dötterl and Schäffler, thirty-six compounds were detected in scent samples from Lysimachia punctata.

Floral oil production is found in some 1,500 to 1,800 species of flowering plants worldwide, in at least 11 plant families, and is thought to have arisen as many as 28 separate times.  Bees benefit from floral oils in two ways: they have a higher energy content than nectar or pollen and, as well as being used to feed the bee’s larvae, they are used to make a waterproof brood cell lining. (The adult bees don’t feed on the oils.) The oils are costly for plants to produce but this is worthwhile if the associated bee pollinates the flowers (note 7).

In England south of a line between The Wash and the Bristol Channel, Yellow Loosestrife’s flowers are attended by the solitary bee Macropis europaea, the Yellow-loosestrife Bee. The female bees have special projections on their basitarsi (the the basal segment of the tarsus) for collecting Yellow Loosestrife’s floral oils.

Yellow-loosestrife Bees were in attendance at Redgrave & Lopham Fen – both males swarming around the plants in search of females and females hard at work gathering pollen and floral oils. (The bees also visit plants such as Creeping Thistle and Water Mint for nectar.)

Yellow-loosestrife Bees nest in the soil, generally in banks or slopes. Nest sites are often at risk of flooding but the developing larvae and pupae are protected underground by a waterproof cell lining made from the floral oils. In Surrey, David Baldock found a Macropis europaea nest site at least 300 metres away from the nearest Yellow Loosestrife, and when he planted a single plant of Yellow Loosestrife in his garden pond, a male Macropis europaea visited within a week, even though he knew of no nesting sites or even Yellow Loosestrife within two miles of his garden (note 8).

A female Macropis europaea at work in a Yellow Loosestrife flower.

A female Yellow-loosestrife Bee (Macropis europaea) at work in a Yellow Loosestrife flower.

Yellow Loosestrife has a number of potential medicinal uses, listed on the Plants for a Futrue website, including “a serviceable mouthwash for treating sore gums and mouth ulcers”, to treat gastro-intestinal conditions such as diarrhoea and dysentery, to stop internal and external bleeding and to cleanse wounds. A yellow dye can be made from the flowers and a brown dye from the rhizomes. The plant has also been burnt in houses in order to repel or remove gnats and flies. The plant is described as astringent but a subspecies (Lysimachia vulgaris davurica) is grown in China for food.

As well as Redgrave & Lopham Fen, Yellow Loosestrife and its bee occur at other sites in Norfolk, including many of the Broads and at Strumpshaw Fen RSPB Reserve and on Beeston Common, near Sheringham.

If you want to grow Yellow Loosestrife, Emorsgate Seeds sell the seeds, which can be sown at any time of year. Grow it somewhere damp in a clay soil in sun or semi-shade and it should do well. If you live in the south you could even attract its attendant bee.

Notes

Note 1 – We were able to visit the northern half of the reserve (Lopham Fen) without needing our passports, as it lies in Norfolk. We had mainly gone to see invertebrates, including another attempt to see the Fen Raft Spider, Dolomedes plantarius

On previous trips to Redgrave & Lopham Fen in 2018 (including one by train from Norwich to Diss followed by a taxi ride), we failed in our quest, as the pools where the spider lives had mostly dried out. We finally found an immature specimen at Carlton Marshes, another Suffolk Wildlife Trust reserve near Lowestoft, in September 2019.

This year there was plenty of water and we managed to see two Fen Raft Spiders, one of which is pictured below.

Fen Raft Spider, Dolomedes plantarius

Fen Raft Spider, Dolomedes plantarius


Note 2 – The UK Wildflowers website gives an example of Yellow Loosestrife being outcompeted by Common Reed (Phragmites australis) at Hatchmere Lake in Cheshire. Regular cutting of reed, as at Redgrave & Lopham Fen, will presumably assist Yellow Loosestrife by keeping the reed bed more open.

Note 3 – Fourth Edition, 2019. Several are introductions, including the frequent garden throwout Dotted Loosestrife, Lysimachia punctata.

Other species of Lysimachia that I encounter in Norfolk are Bog Pimpernel (L. tenella, pink flowers, boggy, peaty ground), Scarlet Pimpernel (L. arvensis, scarlet flowers, a “weed” of arable land and gardens), Creeping Jenny (L. nummularia, damp places but surviving in shade in our back garden) and Yellow Pimpernel (L. nemorum, in woods. It “creeps” like Creeping Jenny but the leaves are more pointed).

I grow a form of Fringed Loosestrife, Lysimachia ciliata ‘Firecracker’, in the garden. It is far too dry for it on my sandy soil with minimal rainfall, even in semi-shade. I have to water it regularly in summer, but I like its contrasting purple leaves and bright yellow flowers.

When I first learnt plant names, Bog Pimpernel and Scarlet Pimpernel were both in the genus Anagallis.

Note 4 – Lysimachus means “scattering the battle” in Greek, and Wikipedia mentions several people of that name. To add to the confusion, one of them even founded a Greek city called Lysimachia (now in modern Turkey) and the First Nature website says that the plant was named after him, rather than the Sicilian king.

Note 5 – According to Merriam-Webster, “loosestrife” is intended as translation of Greek lysimacheios loosestrife (as if from lysis act of loosing + machesthai to fight).

Note 6 – Schäffler, F. Balao,and S. Dötterl studied a number of Lysimachia species and Table 1 in their paper lists which species produce floral oils. Lysimachia vulgaris produces them, as do L. punctata, L.ciliata, L. nummularia and L. nemorum. L. arvensis, and L. nemorum don’t.

See I. Schäffler, F. Balao,and S. Dötterl (2012), “Floral and vegetative cues in oil-secreting and non-oil-secreting Lysimachia species”. Ann Bot. 2012 Jul; 110(1): 125–138.

Note 7 – Much of my information on floral oils and bees comes from Bryan N. Danforth, Robert L. Minckley and John L. Neff’s superb book “The Solitary Bees – Biology, Evolution, Conservation” (Princeton University Press, 2019), particularly pages 177 – 186.

Worldwide, 440 species of bee have become morphologically and behaviourally specialised  upon oil-producing host plants.

Other plant families with species that produce floral oils include the Orchidaceae, Plantaginaceae, Scrophulariaceae, Cucurbitaceae and Iridaceae.

Note 8 – I highly recommend the late, great David Baldock’s book “Bees of Surrey” (Surrey Wildlife Trust, 2008).

Weld, Reseda luteola

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Weld, Reseda luteola

A group of Weld, Reseda luteola, plants growing at the edge of a field near Norwich (mid June 2020).

In the last couple of years I have grown Weld, Reseda luteola, in the garden.

Weld is a biennial. In its first year it forms rosettes of narrow, dark green, shiny leaves. These have a prominent white mid-rib and are often crisped and wrinkled like angled aluminium tent pegs. Below ground, the plant forms a long tap root.

In its second year, Weld grows upwards, producing flowering shoots to 1.5 metres (5 feet) high or sometimes more. These often branch towards the tip and bear racemes of pale yellow flowers from June onwards. As the plant ages the plant often takes on an orangey-yellow tinge, as the rear plants have done in the photograph above.

In the British Isles Reseda luteola is thought to be an archaeophyte (an ancient introduction). It is native to Eurasia and parts of North Africa, including Egypt and Libya, Portugal, Spain, Albania, Bulgaria, Greece, Italy and the former Yugoslavia, Afghanistan, Cyprus, Iran, Iraq, Turkey and Pakistan. It has been introduced into North America and parts of Australia.

Weld is a member of the Resedaceae, the Mignonette family. Worldwide, the family contains 107 known species in 8 to 12 genera, but in Britain we only have five species of Reseda and you’re most likely to encounter just two of them: Weld (Reseda luteola) and Wild Mignonette, Reseda lutea (note 1).  Wild Mignonette is also a biennial but it is a shorter plant with divided leaves. My way of remembering the difference between the plants is that Wild Mignonette has divided leaves but Weld’s are entire – as if they have been welded together.

I grow Weld in the garden because I like its flowers and its upright growth habit, which allows it to fit into fairly small spaces, a useful habit if you want to grow a wide range of plants.

But my main reason for growing Weld is to attract Yellow-face (Hylaeus) bees, especially the Large or Mignonette Yellow-face Bee, Hylaeus signatus. In Britain the female bees only collect pollen from Weld and Wild Mignonette and even a single plant (which is all I have room for) will attract the females and also groups of males, which swarm around the flower heads in the hope of finding mates. Today is cool and damp so they have just been sitting on the flowers, but on a hot sunny day the males whizz round and round the flowers. There are twelve species of Yellow-face bees in the British Isles and nine in Norfolk; we get seven species in our garden in Norwich. Hylaeus signatus is the largest and Weld also attracts Hylaeus pictipes, the Little Yellow-face Bee, which we re-found in Norfolk in 2017 in our garden, after an absence of over a hundred years.

Large or Mignonette Yellow-face Bee, Hylaeus signatus

Large or Mignonette Yellow-face Bee, Hylaeus signatus, on Weld flowers.

Hylaeus signatus and Hylaeus pictipes

Little and Large: Hylaeus pictipes (bottom left) and Hylaeus signatus on Weld flowers.

In the British Isles, Weld grows on neutral or base-rich soils, which means that it becomes much scarcer in Highlands of Scotland and in western Ireland. The Online Atlas of the British and Irish Flora lists its habitats as:  roadsides, waste ground and marginal land, in brick yards, gravel-pits and urban demolition sites, and, less commonly, arable or grassy areas.

Weld is a useful dye plant and it has a history of use from at least the first millenium BC and was reputedly used to dye the robes of the Vestal Virgins in Roman times. Nowadays synthetic dyes have mostly taken its place but the plant is still grown for this purpose. It contains significant quantities of the flavonoid luteolin, a yellow dye (note 2). Another name for the plant is Dyer’s Rocket.

The leaves or seeds of Weld are used to produce dye (note 3). The Plants for a Future website says that “the plant is harvested as the last flowers fade. Most of the dye is found in the seed.” The Wild Colours website advises that “the colour is more concentrated in the leaves, flowers and seed capsules; the stalks do not have much colour. Old, dried-up weld plants give a dull yellow.”

The Dyeing Crafts website says “Cut the plant about 10 days after the start of it flowering. The leaves, flower heads and seed capsules provide the maximum dye content. The plant can be used fresh or dried for storage to be used at a later date.” It also gives a recipe for making the dye.

I grow my Weld plants from seed. I buy mine from Emorsgate Seeds, but there are plenty of other suppliers if you do an internet search. I sow my seeds in late summer in peat-free compost in an unheated greenhouse and transplant them to their final home in late winter, before the tap root is too long. It is important not to cover the seeds with too much compost, as they need light to germinate. Seeds can also be sown in spring. Plug plants are also available from companies such as Naturescape. (I haven’t tried these, but it would be a quick way of establishing plants.)

If you want to produce a green dye (such as Lincoln Green) you can mix the yellow dye from Weld with the blue dye from Woad (Isatis tinctoria).

With apologies to Louis Armstrong, “And I think to myself what a wonderful Weld“.

Notes

Note 1 – Stace (Fourth Edition, 2019) lists Reseda luteola (Weld), R. lutea (Wild Mignonette), R. alba (White Mignonette; casual on waste ground), R. phyteuma (Corn Mignonette; rare and decreasing casual of waste ground) and R. odorata (Garden Mignonette; occasional garden escape).

Note 2 – Weld also contains two other dyes: apigenin and chrysoeriol.

Note 3 – The seeds also contain an oil that has been used in lighting.