Ecological Flora of theCentral Chilterns
Section 38: Asteraceae subfamily Asteroideaetribes Gnaphalieae, Inuleae, Astereae
Ploughman's spikenard with leaves mined by the fly Phytomyza conyzae. Photo by Val Marshall.
38.1Tribe Gnaphalieae (Cudweeds)
Marsh cudweed Gnaphalium uliginosumNative annual not infrequent in damp tracks and moistcorners of arable fields (not usually on chalk).Identification Like all in this tribe, the flower-heads lackouter ray petals, ie they are like the centre of a daisy, with"disc florets" only. They are low plants with almost linearleaves densely covered, like the stems, in grey-white hairs,the flower-heads yellow-brown and overtopped by theleaves on the tips of short side branches.Notable sites Mostly in clay arable land in several fieldsaround Great Hampden, Brickfields and Peterley; alsorecorded from the main ride in Monkton Wood, theallotments at Greenlands Lane and even on the Lovell Estate.Galls Only two galls in the flower-heads are known, and oneis very rare. Neither is reported from our area.Mines No mines have been recorded from Gnaphaliumspecies in Britain.Other ecological associates Not observed to be visited byinsects.Human associations None known. (This plant appears toexist in an ecological vacuum!)Derivation Although it likes damp spots on bare soil, it isnot found in marshes as such. A former name of WaysideCudweed better expresses its liking for trampled paths.The origin of "cudweed" is problematic, with various guesseshaving been made, but the one that appears to carry mostweight is its being a contraction of "cotton-weed" (an oldalternative name referring to the appearance of the leaves).
Heath cudweed Omalotheca sylvaticaNative perennial of bare places on acid soil, nowextremely rare in the county and probably no longer inthe Chilterns (last seen 1995). It was recorded in"Prestwood" in 1924 by James Britten. It was probablymore common in the early C19th before the enclosure ofthe commonlands. It is unbranched and the flower-heads are in more elongated clusters (or single) at thebase of the leaves.
38.2Common cudweed Filago germanicaNative annual of bare ground, usually on sandy soil.Druce (1926) described it as "locally common" in ourregion, but it is now very far from common and, like thelast species, quite possibly extinct in the Chilterns,probably for the same reason, the loss of heathlands tobuilding. It has leaves crowded up the stem and denseglobular flower-heads on side-shoots standing above theshort leaves. The last local record was in 1952.
Small unbranched specimens (Greenham Common)Photo by Val Marshall
Tribe Inuleae
Ploughman's spikenard Inula conyzaeNative perennial of scrub, long grassland and woodlandrides, but always on chalk; quite local in our area.Identification Tall, rather coarsely hairy plant, itsupper leaves clasping the stem, the lowest in a rosetteover winter, looking very much like foxglove, butwithering by flowering time. The yellow-brown flowerslack rays and are in well-branched open clusters, almsotan umbel, their bracts, like the stems being purplish.Notable sites Hampdenleaf Wood, Prestwood PicnicSite, Hatches Bank, Longdown Bank and besideHampden Road.Galls Only one gall has been recorded on ploughman'sspikenard in south England, and that is rare. It has notbeen seen locally.Mines Of five leaf-miners known in southern Britain,two occur locally. Phytomyza conyzae is the dominantone on this plant in our area, although Chromatomyiasyngenesiae also occurs.Other ecological associates None reported.Human associations The roots are aromatic and weretraditionally hung in cottages to freshen the air.Derivation "Spikenard" was taken from the name of acompletely different Asian plant that was used to makea popular aromatic ointment (nard): so our plant is thepoor man's substitute for this. Photo at Hatches Bank by Val Marshall
38.3
Detail of flower umbel from above
Ploughman's spikenard
Mines of Chromatomyia syngenesiae
Elecampane Inula heleniumPerennial introduced from Asia in prehistoric times, continuingalong waysides and field edges, although increasingly rarethroughout the country. Druce (1926) said it was "very rare" inour region and it has not been seen here since that time; nor amI aware of any recent instance in the Chilterns generally,although I saw it twice in west Berkshire in 2013. It is a verytall robust unmissable plant with huge daisy-like yellow flower-heads nearly 10cm across, with very narrow ray flowers. It isvery popular with bees and hoverflies. It was introduced for itsaromatic starchy roots that were used as subsistence food andto make a medicine for coughs and chest complaints. Itsprincipal chemical component inulin (from the Latin genus) isused in modern treatments for asthma. "Elecampane" is acorruption of the medieval Latin name for the plant - inulacampana, or "Inula of the field". The Latin inula in fact meant"elecampane" on its own. It derives from the Greek helenionfor the same plant, thought to be named after Helen of Troy,famed for her beauty. It cannot be coincidence that thesyllable hel (with a short or long "e") is common to the nameHelen and the Greek words for sun, moon and torch, so that theunderlying meaning would have been "radiating light or beauty".
38.4Common fleabane PulicariadysentericaNative perennial of wet places, said byDruce (1926) to be "frequent", but thefact that only four local sites have beenrecorded for it in this century, is a clearindication of the drying-out of ourenvironment, from a diminished water-table and excessive extraction from theaquifer by water companies to serve anexpanding population. It is common inmarshes along the Thames Valley.Identification Like a small elecampane,common fleabane has hairy wrinkledleaves and flower-heads up to 3cmacross.Notable sites It has gone from twosites recorded in the 1990s, which leavesthe only recent records being Doctor'sMeadow, Little Missenden (2001),Acrehill Field, Bryants Bottom (2003),Speen Access Land (2008) andHughenden Valley (2010). With no morerecent records it is urgent to checkwhether it still grows at any of theseplaces. It is plainly at great risk ofextinction in our area.Galls Both the known British galls arerare and neither is recorded from ourarea.Mines Of the five leaf-miners thatmight be expected, we have recordedtwo - Chromatomyia 'atricornis' andPhytomyza conyzae.Other ecological associates Flies, andplant-bugs like the common Anthocorisnemorum, are much attracted to theflowers.Human associations The Latin genusfrom pulex "flea", literally "related tofleas", and the English name meaning acure for fleas, derive from the beliefthat it could be used to repel fleas. Theleaves have a strong medicinal smell andcould be dried and hung up in the houseor burned on the fire to fumigate a room.Concrete references to such practices,however, are rather rare, so perhaps itdid not live up to its reputation. Thebelief may have come from theobservation that insects sometimesswarm upon it, so that it might lure suchpests away.
Dark twisting mines of Phytomyza conyzae are just distinguishable on a couple of leaves
Flower-head with Anthocoris nemorum feeding on the disc florets
38.5Tribe AstereaeDaisy Bellis perennisCommon native perennial of all sorts of short grassland, most notoriously including lawns.Identification The daisy is so familiar it is almost the archetypal flower. A crowd of white ray florets (oftentinged red at the tip outside) surround a bright yellow dome of disc-florets. All the leaves are in a basal rosette,widely spoon-shaped with a few blunt teeth. This rosette is well-suited to avoid even the lowest mower-blades,and it can throw up flowering stems quickly after mowing.Notable sites Apart from garden lawns and well-mown road verges everywhere, the daisy can be found in grassywoodland glades (Hampdenleaf Wood), chalk slopes (Prestwood Picnic Site, Meadsgarden Field), churchyards andcemeteries (Prestwood, Great Hampden, Great Missenden, Cryers Hill), and the edges of allotments (GreenlandsLane, including Kiln Common Orchard and Prestwood Nature's demonstration wildlife garden).Galls Four fungal galls are known, one occurring only in grasslands that also have wood-rush (Luzula spp). The onlyone found locally has been the regularly-occurring Synchytrium aureum, which causes red leaf-spots.Mines Of the five confirmed leaf-miners on Bellis in Britain, four have been located in our area: the fliesCalycomyza humeralis, Chromatomyia 'atricornis', Liriomyza pusilla and Napomyza bellidis.Other ecological associates A variety of small insects visit the flowers.Human associations Sheer ubiquity is no doubt the reason for this flower featuring in a number of old children'sgames, like making daisy chains. While some who want bowling greens for lawns may object, most people find thesprinkling of white across a sea of green a joyful sight. It has occasionally featured in folk medicine, but it isdoubtful whether it was an effective cure for anything. Maybe it did a power of good to those who firmly believedthat eating a few heads would rid themselves of boils and toothache.Derivation From Old English daeges eaga, "day's eye" - from the fact that the ray-florets close up over the yellowcentre when it goes dark. The word "daisy" is used for a number of similar flowers, although botanically it iscustomary to use the simple name without any qualification only for Bellis perennis.Variation Flowers with several rows of ray-florets (flore pleno) are descendants of garden cultivars thatsometimes escape, which may have larger flowers and more red colour.
Mines of Chromatomyia 'atricornis' Puparia of Chromatomyia Mine of Liriomyza pusilla
38.6Blue fleabane Erigeron acrisNative annual or biennial of chalk grassland, especiallywhere there are bare patches, and calcareous roughground. Not all that common in our area.Identification Medium tall (60cm) plant with stiffrough purplish stems with flower-stalks branching offat the top. The rays and bracts of the small flowersare pale mauve and often remain more or less erect,not exposing the yellow disc. When fully open andalmost white in colour they resemble small daisies.The leaves up the stem are short, linear and wavy.Notable sites It appears regularly at two main localsites - Warren Field (Hampden Bottom) and GreatMissenden Station. There are recent records fromthree other fields at Hampden Bottom, plus StonyBank, and Hampdenleaf Wood.Galls Two galls are known, one rare, neither recordedin our area.Mines The two leaf-miners known for certain in ourregion are both recorded locally: Chromatomyia'atricornis' and Calycomyza humeralis.Other ecological associates None have beenwitnessed locally.Human associations None.Derivation The name of this species and othersfollowing derives from a vague resemblance to commonfleabane, but they do not have any of its chemicalproperties.Variation Our local plants are subspecies acris. Someplants in wasteland in more urban localities can lookrather different and have been identified in EastEurope as subspecies serotinus. These have moreleaves, closer together, more undulate and oftenrecurved, while the flowers form more or less onehead (corymb) rather than on branches distributeddown the stem (panicle). Specimens I found atNewbury railway station were identified by the Polishbotanist Artur Pliszko (see Pliszko 2015) as serotinus,a taxon not generally recognised by British botanists.
Subspecies serotina, Newbury station car-park
Mexican fleabane Erigeron karvinskianus 38.7Introduced perennial from Mexico, long established in the Channel Islands but now gradually moving northwards asthe climate warms. Spreads from gardens and naturalises on bare ground (walls, pavements) where the micro-climate, usually sheltered by walls, is amenable. It is well-established in the Mediterranean.Identification Floppy trailing plant with leaves along the stem and daisy-like flowers whose rays are very palepurple to white above and darker purple beneath.Notable sites Established in the High Street and Church Street, Great Missenden, since at least 1997 and inFriars Walk, Prestwood since at least 2007; also recorded in Hughenden Valley in 2010.Human associations Garden plant intended for rockeries and walls, but readily spreading in frost-free places.
Canadian fleabane Erigeron canadensisAnnual accidentally introduced from North America about 250years ago, but given a particular boost at the time of the SecondWorld War with the arrival of soldiers from Canada and theUSA. It now crops up regularly in urban streets, having becomeparticularly common in London, although somewhat out-competednowadays by even newer arrivals of the same genus.Identification Tall spikes of crowded whitish, insignificant-looking flowers with greyish hairy leaves.Notable sites Regularly occurring all over Prestwood and GreatMissenden residential areas, usually in the edge of pavements.Galls None.Mines The two confirmed British miners are both present locally- Chromatomyia 'atricornis' and Calycomyza humeralis.Other ecological associates Flowers fertilised by small flies.Human associations None.
Mine of Calycomyza humeralis
38.8Guernsey fleabane Erigeron sumatrensisAnnual plant introduced from South America,superseding Canadian fleabane in London and elsewhere,although not yet as common in our area.Identification Like Canadian fleabane but more robust,taller and bushier spikes, wider lower down, sosomewhat pyramidal. The calyx and stem are far moredensely hairy, but the hairs are shorter and less bristly.Hairs at the edges of the leaves are appressed (notstanding up), whereas in E. canadensis they are erect.The narrow base of the leaf has short dense erect hairswith a few erect bristle-like hairs, whereas canadensisonly has longer hairs.Notable sites Our first record was in 1999, HughendenValley, where it has continued to be seen. The nextyear it was seen at Walter's Ash and in 2002 at UpperNorth Dean. It had reached Prestwood by 2008 when itappeared at the Sheepwash, and in 2013 it was growingon the Lovell Estate.Derivation The misleading English name comes from thefact that it was first recorded in Britain fromGuernsey.
Vigorous plant in centre of Newbury 2013
Bilbao's fleabane Erigeron floribundusThis third American import arrived later thansumatrensis but is already just about as common.Identification In hairiness more like canadensis thansumatrensis, and less bushy, but the flower spike tendsto widen towards the top in a diamond shape. Theflowers hardly emerge above the calyx, whose lobes arebroader and blunter than those of canadensis and arevariable in length, not divided into a short outer ruffand long inner lobes like canadensis. Hairs at the leaf-edges are appressed.Notable sites I first noticed it locally in 2014, when asmall plant grew by my front garden path and a few dayslater I found more growing at Peterley Manor Farm,where it continues to appear regularly. In 2016 I foundplants in the gutter of the main road in GreatMissenden (corner of the High Street and MartinsendLane). In 2017 it appeared along Perks Lane.Derivation First noticed in Europe in Bilbao, Spain.Variation A fourth Erigeron from S America isArgentinian fleabane E. bonariensis. It is densely hairy,including long hairs, the calyx is broader and squatter,and it has pink to purple tips to the calyx lobes, a firstgood character for picking it out, although otherspecies may occasionally have this. It has not been seenlocally and is less common in London than the otherthree, but well established in Europe.
38.9
Argentinian fleabane, photographed in Funchal, Madeira
Canadian goldenrod Solidago canadensisPerennial garden escape from North America long-established inBritain. Our single native Solidago, S. virgaurea, does not grow inthe Chilterns, being restricted to acid soils.Identification Tall plant whose yellow flowers occur in long stifflinear spikes branching off the top of the main stem in a distinctivemanner.Notable sites Records this century are from Hughenden Valley,Acrehill Field, Great Missenden station and Prestwood Picnic Site.Seen in the past in Kingshill, Prestwood and Frith Hill.Galls None.Mines Five leaf-miners are likely in our region. The flies Liriomyzapusilla and L. strigata both occur locally.Other ecological associates I have recorded two small plant-bugslocally on this plant - Orius laevigatus and O. niger . Both prey onthrips and mites feeding on the plant, and they have been used asbiological control agents in relation to crops infested by suchcreatures. Escaped goldenrod could therefore act as a reservoirfor these insects in crop-growing areas.Human associations Although formerly (Victorian times) a popularcottage garden plant, its ability to seed and spread prodigiously hasmade it less popular of late, but by then it was well-established inthe wild, especially along the Thames valley.
38.10Early goldenrod Solidago gigantea ssp.serotinaSimilar to the last species and another North American introduction, although less common in the wild. It differsby having hairless leaves (except the veins underneath) and upper stems - both hairy in S. canadensis . It has beenrecorded in Hughenden Valley, Warrendene Road and Angling Spring Wood.
Common Michaelmas-daisy Symphyotrichumx salignumPerennial garden hybrid frequently escaping on to roughland, where it can form thickets. Our two nativeSymphyotrichum species (formerly Aster) arerestricted to the coast.Identification Tall plant, flowers with the ray-florets(usually pale) blue-purple and disc-florets yellow.Notable sites Recorded from Bryants Bottom Road andLodge Wood.Galls It can be galled by a recently introduced mite(since the 1960s), but this is not recorded locally.Mines About eight miners are known on cultivatedAster in Britain. The common Chromatomyia 'atricornis',Liriomyza strigata, L. pusilla and Calycomyza humeralisall occur in our area.Human associations Often grown in cottage gardenswith Canadian goldenrod and equally prone to spreadwithin the garden and beyond.Derivation Michaelmas occurs late September and thisplant flowers from August to October.
Narrow-leaved Michaelmas-daisy Symphyotrichum lanceolatumGarden escape, originally from North America. Recorded in Great Missenden in 1997. Ray-florets very pale towhite; leaves less than 1cm wide and not clasping the stem (as they do in Symphyotrichum x salignum).
Narrow-leaved Michaelmas-daisy growing by the Grand Union Canal
38.11Late Michaelmas-daisy Symphyotrichum x versicolorAnother garden hybrid, recorded by the roadside ditch in Green Lane, Prestwood in 2013 (15 October) and stillthere. Like S. x salignum but its middle leaves are up to five times as long as wide and clasp the stemconspicuously, whereas salignum leaves are up to ten times as long as wide and only narrowly clasp the stem, whichis usually stiff, almost hairless and red. It may not start flowering until well into September and still be fresh inOctober (hence the common name), but it often flowers in midsummer too.
There are many more garden varieties of Michaelmas-daisy that almost certainly occur in the Chilterns.
Late Michaelmas-daisy
