Ecological Study of Fritillaria meleagris

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392

SOME FLORA RECORDS

Lathyrus aphaca. Dr. Eastwood found a solitary specimen of this last year near his garage at Oulton Broad and thinks it was probably from seed brought in with mud on his car wheel. Catapodium rigidum, quite common : Mr. Simpson says this is the up-to-date name for Desmazeria rigida, Festuca rigida, Poa rigida or sometimes Sclerochloa rigida. However, I do rejoice to have found this pretty little grass in Ipswich, on my way to post my Sunday letters, under a new alias. Mr. Simpson added that there is another species Catapodium marinum found in almost every maritime parish from Felixstowe to Yarmouth and on sandy heaths and in Breckland and yet no one has recorded it anywhere ! Hypochaeris maculata found by Mr. Bendix at Risby. Mr. Bettridge sent me a specimen from near Sudbury last year. These are our only two records of this for Suffolk. Phytolacca decandra, American Poke Weed. Mr. R. W. K. Kefford found this stränge plant in his garden at Wickham Market and brought it in for Mr. Simpson to name. It is a native of Virginia, but Bonnier has it as a naturalised casual and cultivated in the South of France. The flowers of this specimen were a pinkish purple in dense Clusters, in shape like an old fashioned poke bonnet. Mr. Mitchell reported last year that Mrs. Lynnch had found this plant on May 26th, 1953, on waste ground at the I.C.I. Factory at Stowmarket. With apologies in anticipation of reproach if I have omitted other interesting things, but be assured they are all carefully recorded. More, please. I

AN ECOLOGICAL STUDY OF FRITILLARIA MELEAGRIS L. b y P. J. O .

TTIST.

THE Fritillary or Snake's Head, is now a very localised plant in Suffolk. In pre-war days it was more plentiful and able to flourish in damp pastures which have now been drained and ploughed. The purpose of this note is to record the plant ecology of the Framsden and Mickfield meadows which are probably the only remaining strongholds of Fritillaria meleagris in Suffolk.


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The Framsden meadow lies in a small Valley on the chalky boulder clay. Its soil is an organic loam with a pH 7.4 which denotes a high lime content : ifis low in available potash, very low in available phosphate and is fairly typical of the general status of much of the few remaining old pastures on the boulder clay in the County. A main watercourse runs through the centre of the six acres and was last cleaned out in 1956. Its present condition is fair, but not deep enough to avoid the flooding which occurs annually from December to January and Covers the whole field except the raised headlands. In the years following the cleaning out of the main ditch, it has been noticed that the total number of flowering fritillaries has increased. At Framsden on 18.3.60, the length of the fritillary stems was 7.5-12.5 cm. The flower buds were 1-2 c.m in length. The great majority of the plants at this date had not finished development and leaves were still in the compact S t a t e with no perianth showing. By the 4th May, the stems were Âą 2 5 cm. long and the perianth 4-5 cm. A few plants remained in closed bud but the majority were past their best in flower. From observations made by Mr. & Mrs. G. F. Fox of Boundary Farm, over the past forty years, the fritillaries are annually in flower from the middle to the end of April. There are some earlier flowering plants which have been growing in the shade of a hazel tree in the farm garden, in a dry position 2o feet clear of the surface of the water in the moat, and these are known to have been there for over forty years. By contrast these plants are annually in flower at the end of March, one month earlier than those in the low meadow. The soil texture is similar but with a higher pH 7.8, low available phosphate as opposed to very low status in the meadow, and a medium available potash compared with a low status in the meadow. On the 18th March the perianth development was 2-3 cm. in length (meadow 1-2 cm ) with length of stems 15-20 cm. (meadow 7.5-12.5 cm.). The plants in the garden are never picked and their numbers remain about constant. In the meadow, it is considered that there is little V a r i a t i o n in the total plant population from year to year and the botanist is grateful to Mr. Fox for his management of the meadow, which is designed to preserve the fritillaries. It is laid up annually for rough hay until the fritillary stems have fallen and the seeds dispersed, and cut in July. In 1960 it was cut earlier than usual, on July Ist, but the following weather was unkind and the product for the naturalist /farmer was poorer than usual. Latpr it was learnt that an opportunity to pick up the hay never came. The great majority of the flower heads in 1960 were dull purple in colour and solitary. Single white forms occur, and paired purple flowers and paired white forms are also found. On the


AN ECOI.OGICAL STUDY

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4th May, twenty square-yard areas were recorded for plant population, which ranged from 6 to 22 fritillary plants per Square An estimate of the number of plants in the meadow in 1960 is 45,000-50,000 per acre. Most of the meadow is fairly evenly colonized by fritillaries with the exception of a small low area near the central ditch which is flooded for a longer period and densely colonized by Filipendula ulmaria, together with Carex hirta and Carex nigra and where there are few fritillaries. T h e dominant plant in the sward is Alopecurus pratensis ; Filipendula ulmaria occurs all over the meadow and was checked by an M C P A spray in 1957, but the density of these plants has now regained its former position. T h e meadow is surrounded by tall hedges and its position on the farm lends itself as a quiet corner for wood pigeons which, in the area of the meadow headlands, had damaged plants by petal Stripping or biting the flower head clean off in all stages of growth. T h e following plants are found in the meadow sward, on slightly higher ground by the hedges and in the watercourse. Alopecurus pratensis L. A. myosuroides Huds.

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Holcus lanatus L. Poa trivialis L. Loliurn perenne

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L.

Festulolium loliaceum {Huds.) P. Fourn Dactylis glomerata L. Bromus mollis L. B. thominii Hard. B. commutatus Schrad. var. pubens

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Festuca rubra L. subsp. rubra F. pratensis Huds.

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Anthoxanthum odoratum L. Glyceria fluitans (L.) R. Br. Phalaris arundinacea L.

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Brachypodium sylvaticum Agrostis stolonifera L. A. gigantea Roth.

{Huds.)

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Arrhenatherum elatius (L.) J. & C. Preel. Cynosurus cristatus L. Phleum pratense L. Hordeum murinum

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395

AN ECOLOGICAL STUDY

Briza media L. Trisetumflavescens(L.) Beauv. Agropyron repens (L.) Beauv. A. repens var. aristatum Fritillaria meleagris L. Filipendula ulmaria (L.) Maxim Rumex obtusifolius L. R. acetosa L. R. hydrolapathum Huds. Heracleum sphondylium L. Anthriscus sylvestris (L.( Hojfm. Urtica dioica L. Ranunculus acris L. R. bulbosus L. R. repens L. R.ficariaL. Cirdum arvense (L.) Scop. Achillea millefolium L. Trifolium pratense L. Lathyrus pratensis L. Vicia cracca L. Lotus corniculatus L. Hypericum perforatum L. Geranium dissectum L. Veronica chamaedrys L. Carex Lizta L. C. nigra (L.) Reichard Juncus effusus L. J. inflexus L. Luzula campestris (L.) DC. Caltha palustris L. Plantago lanceolata L. P. major L. Orchis mascula (L.) L. Cardamine pratensis L. Tragopogon pratensis L. Bellis perennis L.

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396

AN ECOI.OGICAL STUDY

Centaurea nigra L. Lychnis flos-cuculi L. Primula veris L. Mercurialis perennis L. Taraxacum officinale Weber. Galiurn aparme L. Lamium album L. Stachys sylvatica L. Epilobium hirsutnm L. Equisetum palustre L. Cerastium vulgatum L. Ajuga reptans L. Alliaria petiolata (Bieb.) Cavara and Grande Potentilla reptans L. a=Abundant f=Frequent T h e Mickfield meadow which Promotion of Nature Reserves, in the preservation of Fritillaria records that he has known the thirty years.

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o=Occasional r=Rare is owned by the Society for the presents a very different picture meleagris. Mr. F. W. Simpson plants to be there for the past

T h e soil status of the Mickfield meadow is slightly different from that of Framsden. The soil type is similar, an organic loam, but with a p H 6.8 : there is no lime requirement and the available phosphate is very low (Framsden very low) and the available potash is very low (Framsden low). T h e field lies on a gentle slope facing north. At the lower end a watercourse, which was cleaned out in 1956 and is now maintained in good order, prevents winter flooding of the lower part of the field. Until 1960 when some scrub was cut down, the field had had no management for some years and had been allowed to revert to briars and brambles with small thorn and oak which, although by no means thick, would eventually have had a competitive effect on the flora. It is important to note that this scrub growth effectually prevents mowing for hay and even eifective grazing. In a record made of the condition of the field in 1953, fritillaries were to be found all over the field and it was then either cut for hay or grazed down at sometime during the season. In early May, 1960, flowering fritillaries were confined to an area of about half an acre on the west side. There has been considerable loss of flowers due to wood pigeon damage and it is likely that the burning of scrub and grass in mid March had damaged fritillary


AN

ECOLOCICAI,

STUDY

397

stem growth, which at Framsden on 18th March was already 7-12 cm. long. The lower half of the field is now dominated by Filipendula ulmaria and there were no plants of Fritillaria to be seen there in 1960. The Alopecurus pratensis dominant at Framsden, is at Mickfield confined to small areas, where it has grown into aggressive plants surrounded by dead mat debris. There are no Fritillaria meleagris in areas colonized by Agrostis stolonifera and where Dactylis glomerata and Deschampsia caespitosa have made " tussock " growth ; the latter, together with Chamaenerion angustifolium and Epilobium hirsutum, has increased their areas in recent years. Mr. Simpson records that the proportion of flowering to non-flowering plants " has remained fairly constant for several years " but it is obvious that with the increasing cover of scrub, the population of Fritillaria plants has become less and the percentage of non-flowering plants has increased. Mr. Simpson also records that in 1958 and in other wet years, more flowers were seen in the upper than in the lower part of the the field, i.e., in areas where there is a more open " sward ". The following plants found at Mickfield in association with Fritillaria meleagris have been recorded by Mr. Simpson, but do not represent a fßll list :— Hypericum perforatum L. Centaurea nigra L. Achillea millefolium L. Silaum silaus (L.) Schinz & Thell. Anemone nemorosa L. Listera ovata (L.) R. Br. Ranunculus auricomus L. Primula veris L. (decreased) P. vulgaris L. (now v. scarce) Mercurialis perennis L. Cirsium arvense (L.) Scop. C. palustre (L.) Scop. Cardamine pratensis L. (now v. scarce) Ajuga reptans L. Viola riviniana Reichb. (scarce) Ophioglossum vulgatum L. (rare) Solanum dulcamara L. Anacamptis pyramidalis (L.) Rieh. Angelica sylvestris L. Heracleum sphondylium L.


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AN ECOLOGICAI. STUDY

Cerastium vulgatum L. Urtica dioica L. Malus sylvestris Mill. Galium verum L. Chrysanthemum leucanthemum L. Anthriscus sylvestris (L.) Hojfm. Chamaenerion angustifolium (L.) Scop Epilobium hirsutum L. Filipendula ulmaria (L.) Maxim. Dactylis glomerata L. Agrostis stolonifera L. Alopecurus pratensis L. Deschampsia caespitosa (L.) Beauv. Vicia cracca L. V. sepium L. Salix caprea L. S. cinerea L. Ulmus spp. Prunus spinosa L. Thelycrania sanguinea (L.) Fourr. Rubus spp. Rosa spp. Acer campestre L.

COMPARISON OF THE ECOLOGICAL

T h e soil status is fairly similar. fertility is low in both cases.

WATER

STATUS.

There is no acidity and soil

CONDITIONS.

At Framsden the meadow is flooded for three months in the winter and its low position, together with high hedges, excludes it from being dry for more than short periods in the year. At Mickfield, the land would be classified as wet and requiring underdrainage. Only the lower portion was winter flooded and this is now remedied. The top of the field is relatively dry, but the lower half lies wet in the winter. In addition, the scrub and fallen uncut grass, together with dense Covers of Filipendula, excludes light and keeps the soil surface wet throughout the winter.


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MANAGEMENT.

The Mickfield meadow is not cut or grazed. In some parts there is a dense mat of decaying leaf and in others there are aggressive grasses such as Descampsia casepitosa and Dactylis glomerata wh have made tall tussock-like growth. In addition, Epilobium hirsutum and Chamaenerion angustifolium are increasing and together with Rubus spp. and Rosa spp., are creating shade and excluding the grasses. At Framsden, in spite of the presence of Filipendula ulmaria which is kept in check, there is a compact open sward with no bushes. It is cut annually in July and subsequently grazed from August to October. SUMMARY.

Fritillaria meleagrisflourishesin a wet meadow under conditions where there is no grazing or cutting during the active life of the plant. It is tolerant of low fertility and the land may be subjected to prolonged winterflooding,though somewhat less wet conditions are more favourable tofiowering.Its companion plants are preferably grasses and other pasturefloranormally associated with an old and well managed sward. It is essential that a reasonably open sward is maintained by cutting the seasonal growth and where practicable, to follow with autumn grazing so that the sward enters the following season with an even growth and the minimum of dead leaf and stem debris. The lesson to be drawn from these two meadows is that a nature reserve intended to preserve some particular plant or animal must be so managed as to secure conditions which favour the species to be preserved and discourage its competitors. The method devised by two generations of the Fox family has been outstandingly successful, though better drainage conditions to avoid the prolonged winterfloodingwould be more desirable and would reduce the spread of Filipendula ulmaria, the sole competitor in the sward. In contrast the Mickfield meadow, which has been unmown and only lightly grazed on a few occasions since 1953, shows the normal succession of invading plants which takes place in the boulder clay in the absence of cutting, grazing and the application of phosphate. Strong growing grasses such as Deschampsia caespitosa and Dactylis glomerata became aggressive in growth and are followed by scrub leading to afinaljungle of thorns, ash and oak which covered much agricultural land in the thirties. The scrub cutting of 1960 will only postpone for a year or two the inevitable climax if the Mickfield meadow is not managed like the Framsden one in the future.


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