Fern Gazette
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ISSN 0308-0838 THE FERN GAZETTE VOLUME ELEVEN PART FIVE 1977 THE JOURNAL OF THE BRITISH PTERIDOLOGICAL SOCIETY THE FERN GAZETTE VOLUME 11 PART 5 1977 CONTENTS Page ECOLOGICAL NOTES Observations on some rare Spanish ferns iri Cadiz Province, Spain - B. Molesworth-AIIen 27 1 Unl:>ranched plants of Equisetum palustre L. - G. Halliday 276 Cyrtomium fa lcatum naturalised on Rhum - P. Corkh i/1 277 MAIN ARTICLES A pteridophyte flora of the Derbyshire Dales National Nature Reserve - A. Wil lmot 279 Ferns in the Cameroons. 11. The pteridophytes of the evergreen forests - G. Ben/ 285 An ecological survey of the ferns of the Canary Islands - C. N. Page 297 A new record of Synchytrium athyrii on Athyrium filix-femina - E. MUller & J.J. Schneller 313 Further cytogenetic studies and a reappraisal of the diploid ancestry in the Dryopteris carthusiana complex - M. Gibby & S. Wa lker 315 Cytology and reproduction of Ch eilanthes fa rinosa from Yemen -S.C. Verma 325 Lunathyrium in the Azores; a postscript- W.A. Sledge 33 1 SHORT NOTES Dryopteris x brathaica Fraser-Jenkins & Reichstein hybr.nov., the putative hybrid of D.carthusiana x D. fil ix-mas - C.R. Fraser-Jenkins & T.· Reichstein 337 No menclatural notes on Dryopteris - C.R. Fraser-Jenkins & A.C. Jermy 378 REVIEWS 278,329,341,342 [THE FERN GAZETTEVolum e 11 Part 4 was published 1st June 1976] Published by THE BRITISH PTERIDOLOGICAL SOCIETY, c/o Department of Botany, British Museum (Natural History), London SW7 5BD. FERN GAZ. 11(5) 1977 271 ECOLOGICAL NOTES OBSERVATIONS ON SOME RARE SPANISH FERNS IN CADIZ PROVINCE, SPAIN PTERIS SERRULATA Forskal. In an earlier paper, when I published the finding of one plant of this fern, I rather doubted its native status here in southwest Spain as it had not been recorded previously (Molesworth Alien 1967). Later when I found four more plants in another mountain range some kilometers from the first, and in a much less disturbed area I felt that perhaps it was a representative of the vestigial remains of a macaronesian flora that was probably common in these hills and val leys in the past (Molesworth Alien 1971 ). Recently, whi lst in search of an easier access to a high mist-laden va lley in the Los Barrios/Aigeciras mountain complex, I crossed a stream which no doubt flows from this valley and near it found more Pteris serrulata. I counted 98 plants, mostly adult, with in a small area, and with my field glasses, could see others higher up, but did not get to these. Some distance to the left, in a shallow Rhododendron-clad arroyo, were a few large ad ults. Then, near (but not in), a large rocky stream about 100 metres to the north-west, I found a large, dense patch of possibly hund reds of · plants of Pteris, growing with in a narrow strip. So I now have no doubt that th is graceful fern is indeed native to southwest Spain, and this, especially the second place, was a glimpse of what it must have looked like previously in many more of the valleys in these hills. This area is still in a rather inaccessible part of the foothil ls. Cattle and goats have helped to keep the status quo over the centu ries, so that bracken and bramble have not yet taken over. The goats however have gone and trees, especially alder, are being cut. Since fencing is now obligatory where cattle graze, alders are cut for posts, and so it looks as though a new cycle is about to start. There are more openings in these arroyos where the water may dry out more quickly. In the absence of goats, bracken and bramble may become dense, and one can only hope that these rare ferns, I ike Pteris, Diplazium and Cuteita, will be able to survive. In this area the fronds of Pteris serrulata are large (fonds to 147cm (including stipes to 25cm) x 47cm) compared with those described in Flora Europaea (Walker 1964), although many were within this range. The rhizome was immensely thick and long, about 25 x 10cm. 1he pinnae are distinctly caudate. Most fronds have 7:9 and a · very few 10 pairs of pinnae. In the second area, some of the fronds had 11 pairs. The basioscopic pinnae of the lowest pair usually have three pairs of we ll developed pinnules; the basioscopic of these being the largest and sometimes it� lowest segment is either lobed as a minature · pinna or crenate. The acroscopic pinnule may also be enlarged and deeply lobed or crenate. Often the next pair of pinnae have their basioscopic lobes shallowly lobed or crenate or even pinnatifid, but this is less common. P. serrula ta certainly requires a special environment here, for it does not appear to grow in or at the sides of the rocky streams so common in the hill forest, but where there is a permanent seepage or underground water. These places would probably be flooded every winte r for at least a short time. The rocks amongst which they grow are white, sharply angled and moss-covered, and all these localities have a nearby rocky stream which would help to keep up the high humidity. Trichomanes sp eciosum often grows at their bases, and Diplazium caudatum occasionally. Sometimes the seepage is stagnant, but usually the water which is always shallow, moves slowly. As these areas may well be destroyed in the future, for new roads are constantly being built, it may be of interest to record some of the other plants which grow in this 272 FERN GAZETTE: VOLUME 11 PA RT 5 (1977) environment. Most of the first locality is similar to that above Algeciras (Molesworth Alien 1971 ) : tall saplings of Alnus glutinosas, and large, very dense Rhododendron ponticum ssp. baeticum covered with liane-like creepers. Most of it had undoubted ly been damaged in the past as large alders had been removed and some trunks of each Rhododendron cut, but apparently never cleared enough to allow bracken to establish - the greatest erJemy of these rare ferns. Frangula alnus and flex aquifolium L. are mixed with the alders in the upper storey and on the dryer slopes immed iately above, large cork oaks no doubt help to shade the Pteris area. In the damper rocky ground on the edges are large trees of Ouercus faginea ('Quehigo'). Sh rubs include Rhamnus a/a te rnus as well as young holly, Frangula and occasional Laurus nobilis. The creepers are mainly Smilax mauritanica, Rubia peregrina, long free-hanging stems of Hedera helix which also cover the alder trunks, and long shoots of bramble (Rubus ulm ifo lius). Ground plants ani comparatively sparse: .one metre tall Ruscus hypophyllus; a few Osmunda regalis and Athyrium filix-femina, occasional 8/echnum sp ican t and Lamium flexuosum. Carex pendula is frequent, with a few tree seed lings and Iris fo etidissimma, Sib th orpia europaea and the ubiquitous Arisarum proboscidium are here. (The latter is perhaps the commonest ground plant in the wet or seasonally damp areas of the oak woods here, from about 30 to at least 670 m altitude and apparently ha I ted only by direct sunlight). The water which collects from the seepages forms a shallow. swamp on ffat, more open land in three localities. Here lady fern is abundant, also Carex pendula and Ca/litriche stagna/is with small sedges including Scirp us cernuus Vahl and Juncus spp. Mosses on the rocks and on the ground amongst the Pteris serrulata include Th amnium alopecurum, Mnium hornum, M.affine, Fissidens serrulatus and others. Sphagnum was absent, although it would seem to be a suitable habitat, but this genus is extremely rare in southwest Spain. The rocky stream, less than 10 m away, with swiftly flowing water, have similar moss-covered rocks, plenty of Athyrium and Osmunda, but no PtPris . The other main locality about 100 m away from the above one, is in a similar habitat, but the alders are large and cast ample shade together with two mature Ouercus faginea. The Pteris plants dominate a rocky strip. Between them are scattered rhododendrons, and towards the back Frangula, laurel, and alder saplings and a few young figs (Ficus carica). The forest has been completely cut to within 20 m, and a dense border of rhodendrons keeps the secondary.growth from encroaching. No plants grow beneath them. Beyond the dense stand of Pteris, the habitat is open, with scattered Pteris, a few Diplazium, and a single young plant of Trichomanes sp eciosum was wedged between two rocks above underground water. POL YSTICHUM SETIFERUM (Forskal) Woynar was collected in the Cad iz .province during last century, but not recently. lt has not been known from the Algeciras/Los Barrios districth�nless the Po lystich um sp inulosum (L.) Sw. recorded by Allorge (1934) from �he Miel valley was this. I found this fern growing on sloping ground in the Sierra de Qjen, facing roughly north-east, the highest being at 570 rn. Here the fronds are slightly longer and wider than given in Flora E,urop_aqa' by Va.lentine ( 1964) and resemble· the form from the Azores. Although a few of the adults are near streams, the majority are not, and grow in rather loose soil in an area that remains wet during winter, but dry in summer. Scattered around here are 17 plants, mostly adult and fertile and young plants were found establish ing by small. rocks. The habitat is a small patch of sapling forest mainly ECOLOG ICAL NOTES : SPANISH FERNS 273 of tall Frangula, Rhamnus alaternus, Holly, very tall Erica arborea and Cytisus striatus, young cork oaks, Arbutus unedo and laurel trees.