Transactions 1960
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TRANSACTIONS OF THE NORFOLK & NORWICH NATURALISTS' SOCIETY Edited by E. A. ELLIS - MAY VOL. 19 PART 2 5 CONTENTS V The Purple (hybrid) Marram, Ammocalamagrostis baltica, in East Anglia, by E. A. Ellis - - Page 49 Notes on the Vegetation of Blakeney Point, Norfolk, in 1956, by F. W. Jane- ... „ 52 A Salt-Marsh atThornham, in North-West Norfolk, by J. F. Peake - „ 56 Alien Plants from a Norwich Rubbish-Tip, by Ruth M. Barnes- ------ „ 63 New, Rare and Critical Norfolk Lichens (1), by S. A. Manning - -- -- -- „65 Notes on Recently Discovered Remains of Extinct Norfolk Mammals, by Barbara Green - - „ 69 The Grey Seal (Halichoerus Grypus) in Norfolk, by Ruth M. Barnes „ 73 Some Flies 5f the North Norfolk Sea Coast, by K. C. Durrant ,,74 Rare Dragonflies in Norfolk, by K. C. Durrant - „ 76 Some Notes on the Caddis Flies of the Norwich District, by E. T. Daniels - - - - „ 78 List of Members at 31st December 1959 - „ 83 PRICE 5/- Obtainable only from the Society Norwich Printed by the Soman-Wherry Press Ltd., Norwich Published March, 1960 THE PURPLE (HYBRID) MARRAM 49 THE PURPLE (HYBRID) MARRAM, A MMOCALA MA GROSTIS BALTICA (FLUEGGE) P. FOURN. IN EAST ANGLIA By E. A. Ellis From 1792 to 1805, the dunes protecting the lowland country of east Norfolk, from Winterton northward to Happisburgh, were breached by the sea in many places, and the Sea Breach Com- missioners engaged one of the country’s foremost geologists, William Smith, to survey this part of the coast and to direct new coast defence works. In Smith’s report (c. 1805), attention is called to a pecular variety of marram grass found in the area and distinguished from the common kind by possessing broader leaves, very tall stalks and flower spikes “ up to nine inches long.’” It was seen by Smith growing “ inside the dunes ” and he expressed the view that it “ might be taken for a different species.” It seems reasonable to assume, from the description given and from what is known of the local vegetation today, that Smith’s plant was Ammocalama- grostis baltica, which was first described botanically as Arundo baltica by Fluegge in Schrad. FI. Germ. 1, 223 (1806), and later regarded as a hybrid produced by marram ( Ammophila arenaria) and bush grass (Calamagrostis epigejos). H. G. Glasspoole discovered a colony of A. baltica on Caister marrams, just north of Great Yarmouth, in 1885 and this has per- sisted until now. C. E. Salmon and S. W. White recorded that the grass was plentiful along the Norfolk coast from Caister to Winter- ton in July, 1915 ; this is true of it today. F. Robinson reported the discovery of A. baltica on Blakeney Point in the course of an excursion made by the Norfolk and Norwich Naturalists’ Society on May 20th, 1923, but this was based on the misidentification of a " broad-leaved ” form of A. arenaria collected in non-flowering con- dition. I saw this broad-leaved form in flower at Blakeney Point on July 8th, 1956 : the leaves looked broad because they were flattened instead of being curled as in normal plants, but in no case did I find a width of more than 6 mm. In 1953, I inspected most of the dunes along the coast of Nor- folk and Suffolk with a view to plotting the distribution of A. baltica. I failed to discover this grass growing anywhere between Holme-next-the-Sea and Waxham (areas from which it was absent included Scolt Head Island, Blakeney Point and the dunes running south from Happisburgh to Waxham). From immediately south of Waxham to Hemsby it was present more or less continuously. At Horsey, north of the Gap, I found it to be locally dominant not only in both yellow and grey dune areas, but also on sandy knolls stretching inland over sub-maritime fen, where common marram was absent. It was plentiful at Winterton, near the village and on the high dunes running south to Hemsby. There were a few 50 THE PURPLE (HYBRID) MARRAM clumps under low cliffs at Scratby and a few more at Caister. The grass appeared in plenty again in the seaward edge of Yarmouth North Denes near the Caister boundary and it was present in small numbers on new dunes which had developed on the beach adjacent to the North parade during the second world war. A few plants were noticed towards the harbour mouth, on the South Denes. In 1953, the year of the memorable North Sea surge, A. baltica was already established in at least three localities on the coast of Suffolk, namely at the south end of Gorleston cliffs, in grey dunes at Kessingland and (a few plants only) just south of Benacre sluice. I failed to find it between Easton Broad and Dunwich, at Minsmere, Aldeburgh and Thorpeness. The East Suffolk and Norfolk River Board undertook extensive marram planting in the course of repairing the coast defence works immediately following the 1953 surge. Much of the marram used was taken from Winterton and plants of A . baltica from this locality were introduced at many points on the sea banks of both counties, e.g. at Holme, Brancaster, Easton, Southwold, Walberswick, Dun- wich and Minsmere. A few plants which I saw at Gunton, just north of Lowestoft, in 1957, may have been introduced at an earlier date, as may have been those I found at Sizewell in 1958. All the flowering specimens I have seen have resembled one another closely, having purplish panicles, yellow anthers and other features characteristic of the Norfolk, as distinct from the North- umberland and Scottish forms of the hybrid. Whether or not our A. baltica originated through hybridisation in the Winterton- Horsey area (I have not seen C. epigejos there), it appears likely that all the plants growing on the East Anglian coast came from this centre, in some cases through marram planting and in others as the result of living fragments of rhizomes being dispersed by the sea. A. baltica grows well as a pioneer colonist of bare beach sand at the outer fringe of yellow dunes and its drooping leaves collect and hold more sand than do those of the stiffer A . arenaria. It is found persisting in grey dunes and thriving where A . arenaria has become depauperate or has died out, and is also able to grow on sandy peat subject to occasional flooding. It is vigorous in spreading laterally by means of its rhizomes, whereas the rhizomes of the common marram tend to penetrate the sand vertically rather than horizontally. Plants growing within a half-metre radius of A . baltica on Great Yarmouth North Denes, August 14th, 1953 were : Achillea millefolium Agropyron junceiforme x A. pungens. Agrostis tenuis Ammophila arenaria Calystegia soldanella e THE PURPLE (HYBRID) MARRAM 51 Carex arenaria Convolvulus arvensis Corynephorus canescens Dactylis glomerata Daucus carota Elymus arenarius Festuca rubra Galium verum Hieracium umbellatum Honckenia peploides Hypochaeris radicata Jasione montana Leontodon autumnale Lotus corniculatus Ononis repens var. horrida Plantago lanceolata Trifolium arvense Vida cracca Plants closely associated with A. baltica on grey dunes at Winterton, 12th August, 1953, included Ammophila arenaria, Carex arenaria, Corynephorus canescens, Dactylis glomerata, Galium hercynicum, Holcus lanatus, Hypochaeris radicata, Polypodium vulgar and Rumex acetosella. Coreid bugs, Chorosoma schillingii (Sch.) were feeding on flower heads of both common and purple marrams at Winterton in August, 1953. The living leaves of both grasses are commonly parasited by the rust fungus Puccinia ammophilina (Kleb.) Mains, uredospores being found at all seasons. In December, 1958, both uredo- and teleutospores of the crown-rust, Puccinia coronata Corda were abundant on A. baltica on Yarmouth North Denes. The flowers of both marrams commonly bear large horn-like ergots of Claviceps purpurea (Fr.) Tul. in autumn. Other micro-fungi common to these two grasses on the Norfolk coast include Lophodermium arundinaceum (Schrad.) Chev. var abbreviatum (Rob.) Kckx, Tiarospora perforans (Rob.) v. Hoehn., Psammina bommeriae Rouss. & Sacc. Papularia sphaerosperma (Pers. ex Fr.) v. Hoehn. and Tetraploa aristata B. & Br. In the very dry summer of 1959, A. baltica failed to produce flowering panicles almost throughout its territory at Horsey and Winterton. This was the same for A. arenaria except in yellow dunes nearest the sea. In a few damp hollows in yellow dunes, A . baltica flowered normally. This short contribution to knowledge of the history and biology of one of East Anglia’s more interesting and valuable dune grasses is offered in the hope that the purple hybrid marram may receive more critical attention from local naturalists in the future. — e 52 VEGETATION AT BLAKENEY POINT, IN 1956 NOTES ON THE VEGETATION AT BLAKENEY POINT, NORFOLK, IN 1956. By Frank W. Jane A number of points of interest were noted in the flora of Blakeney Point during the summer of 1956 and these are recorded in the present note. Rabbits disappeared from this area during the winter of 1954/5 and it would seem that some changes in the vege- tation may be traced directly to absence of rabbit browsing : others are less readily accounted for, but it is not improbable that some may be attributable to the catastrophic flooding caused by the North Sea surge of 31st January, 1953. Moreover, from June on- ward, the 1956 summer was abnormal, being cool, wet and sunless. There are now numerous vigorous sucker shoots of white poplar (Populus alba L.), produced by the three trees in the plan- tation near the laboratory. This sucker growth was conspicuous in 1955, but in 1956 was even more striking. It does not seem unlikely that such sucker shoots were always produced by these trees, for the plentiful production of root suckers is a well known feature of the white poplar, but that previously their development was checked by rabbit browsing.