Additional plant records from Landguard Common, 1983

ADDITIONAL PLANT RECORDS FROM LANDGUARD C O M M O N , 1983 A . COPPING

The area of Landguard Common studied from 1979 to 1982 (Copping, 1983) was visited at frequent intervals during 1983. Thirty-seven taxa not previously discovered were found. Of these, the majority were colonists or escapes from cultivation, often present in small quantity and unlikely to persist without continual re-introduction. However, up to six additional members of the 'established' flora were noted for the first time, and it was possible to subdivide some previously aggregated species; 316 species have now been recorded since the survey began.

Dates of Visits 19-2,26-3,23-4,7-5,21-5,4-6,11-6,18-6,2-7,18-7,13-8,26-8,17-9, 15-10. The February visit was made to discover if winter-flowering species, particularly Eranthis hyemalis (Winter Aconite) and Galanthus nivalis (Snowdrop), were naturalised. None was found. On 11-6 the writer was accompanied by members of the Wild Flower Society, and on 26-8 by Mr. P. G. Lawson, and acknowledges their help.

Habitat changes Different parts of the recording area were identified by capital letters A, B, C . . . (as shown in the sketch map on p. 375 of the earlier paper) and the same letters will be used in the following account.

Work carried out in the Camping Ground (area G) during the 1982-83 winter resulted in some areas being scraped bare of Vegetation. Many annual species developed there, although detailed recording was possible only in early and late season when few campers were present.

A raised concrete road to the east of Landguard Fort, and just within the western boundary of the recording area, was built in the spring of 1983 to gain improved access to Hall Aggregates' gravel extraction workings. Bare earth at the sides of the road was colonised by a few pioneer species in late 1983 (e.g. Chenopodium vulvaria (Stinking Goosefoot)) and can be expected to produce a rieh crop of ruderals in 1984. Storm water running off this new road will create a damper habitat at the margins than has previously been usual at Landguard.

A heap of fresh top-soil was dumped in B during the 1982-83 winter.

Additions to the Catalogue of Species The nomenclature and order of arrangement again follows that of Excursion Flora ofthe British Isles, (Third Edition) (Clapham etal. 1981).

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ADDITIONAL PLANT RECORDS FROM LANDGUARD COMMON, 1 9 8 3

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Brassica napus spp. oleifera (Rape). Occasional plants escaped from cultivation were found in disturbed places in the north-east corner of the recording area.

Lepidium campestre (Pepperwort). About 10-20 plants on the western slope of X. L. virginicum s.l. Dead remnants of an annual species of Lepidium thought to be L. ruderale (Narrow-leaved Pepperwort), were found in A on 3 - 7 - 8 2 .

A few seeds remained in unopened silicules, and from these two plants were raised in 1983. One was sent to E. J. Clement, who identified it provisionally as L. virginicum s.l.. The other was allowed to mature, and seedlings now in cultivation will provide voucher specimens in 1984. The Landguard plant does not conform well to the description of L. virginicum in Flora of the British Isles (Clapham et al., 1962) and is much closer to that of L. ramosissimum A. Nelson. However, E. J. Clement comments that the group is taxonomically complex and in need of revision, and he is unwilling to attempt a more precise identification. The species was not found at Landguard in 1983.

Coronopus squamatus (Swine-cress). Several plants appeared in G. Thlaspi arvense (Field Penny-cress). One or two plants in B. Cheiranthus cheiri (Wallflower). Two plants in C, close to the new road to the Harbour Viewing Area (HVA). The species is well established on the walls of Landguard Fort, outside the recording area.

Moenchia erecta (Upright Chickweed). A circular patch of approximately 5 ft radius dominated by the species was found in H, but it was not found elsewhere.

Sagina apetala (Pearlwort). Both subspecies were positively identified for the first time. Ssp. apetala (Ciliate Pearlwort) was abundant in K, but appeared to be more restricted in its distribution than ssp. erecta (Common Pearlwort), which was frequent in all the dry areas of short turf in H and S. S. maritima (Sea Pearlwort). Frequent in the lowest-lying parts of K with S. apetala ssp. apetala.

Trifolium hybridum (Alsike Clover). A few plants in A. Lathyrus japonicus (Sea Pea). Several well-established small colonies in V with isolated seedlings present.

Aphanes arvensis s.s. (Parsley Piert). The wet spring encouraged strong growth in this annual, enabling a positive identification to be made.

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Suffolk Natural History, Vol. 20

Rosa rubiginosa (Sweet-briar). Several bushes, previously overlooked, were found on L. R. canina (Dog Rose) seems to be mainly confined to the north of the recording area.

Sedum spurium (a Stonecrop). One or two plants in shingle beside the road to the HVA. Epilobium tetragonum (Square-stemmed Willow-herb). A few impoverished plants in W, confirmed by the appearance of appropriate leaf rosettes in autumn. One or two individuals could doubtfully be referred to E. obscurum (Dull-leaved Willow-herb) and seedlings from them are being raised to provide positive identification in due course.

Coriandrum sativum (Coriander). Appeared in small quantity in A. Polygonum aviculare s.s. (Knotgrass). Found abundantly in G. P. arenastrum (Small-leaved Knotgrass). Firmly identified from G. Records of these members of the P. aviculare aggregate were confirmed by Mrs. E. M. Hyde. However, much 'scrappy' material from widely-separated parts of Landguard was impossible to name with certainty. The aggregate species occurred much more frequently in 1983 than previously.

Rumex acetosa (Sorrel). One plant on a slightly-raised bank immediately to the south of K. R. conglomeratus (Sharpe Dock). One individual, 2 inches tall, beside the road to the HVA. Centaurium erythraea (Common Century). An elongated patch, about 10 x 1 yards, in the north-eastern corner of S. Amsinckia intermedia Fisch & Mey. Several plants on a heap of freshlydeposited soil in B. Calystegia sepium ssp. silvatica (Bellbine). A colony was discovered in the northern part of J. Plants intermediate between ssp. sepium and ssp. silvatica found in 1982 beside the road to the H V A were not seen to flower in 1983.

Linaria purpurea (Purple Toadflax). Small groups of plants in A on the edge of M . O . D . property. A singleton was also found in the southern part of H. Odontites verna ssp. serotina (Red Rattie). One plant in D. Glechoma hederacea (Ground Ivy). One plant, extensively creeping among taller Vegetation, was found in the southern part of H. The extreme scarcity of this species is curious.

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Calendula officinalis (Pot Marigold). One plant in disturbed soil in the north-east corner of the recording area.

Anthemis cotula (Stinking Mayweed). One individual beside the new road to the HVA. Leucanthemum vulgare (Ox-eye Daisy). Found in four scattered locations, the largest colony, of about 12 inflorescences, occurring in July, appeared to suffer acutely from drought in late summer, which may explain its scarcity in, or absence from apparently suitable habitats on Landguard.

Juncus ranarius (Toad Rush) (Confirmed by Dr. C. A. Stace). Up to 12 individuals on mud in the dried-out brackish pool in E - thefirst authenticated Suffolk record for this species.

Festuca arundinacea (Tall Fescue). One clump in A. Lolium perenne ssp. multiflorum (Italian Ryegrass) x L. perenne ssp. perenne (Ryegrass). A few plants alongside the road leading to the HVA would appear to belong here. Lemmas varied from awnless to short-awned within the same spike.

Poa nemoralis (Wood Poa). One tuft of about 20 inflorescences beside the road to the HVA. It seems unlikely to persist.

Bromus hordeaceus ssp. hordeaceus X B. lepidus (Brome-grasses). O sional in newly-disturbed soil in the north of the recording area and probably overlooked before. Found by a member of the Wild Flower Society.

Triticum aestivum L. (Wheat). Scattered individuals beside the road to the HVA. Hordeum distichon L. (Barley). As for the previous species.

Koeleria macrantha (Crested Hair-grass). One tuft beside the road to the HVA. Much of Landguard seems to provide a suitable habitat for this species and it could well become established.

Holcus mollis (Creeping Soft-grass). Dominant over a small area on a low, grassy bank at the southern end of H. Noflowersproduced in 1983.

Agrostis gigantea (Common Bent-grass). One or two plants found in T and another beside the new concrete road east of Landguard Fort. Conditions in T appear to be too dry for this species. Material is in cultivation to provide voucher specimens in 1984.

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92 Suffolk Natural History, Vol. 20 Changes of Status Significant changes affectfivespecies described in the 1983 paper:

Ranunculus bulbosus (Bulbous Buttercup). Extensivefloweringo over much of H and J, and the species appears to be much commoner t previously thought.

Solanum sarrachoides. About 20 plants seen beside the new con Dr. A. C. Leslie (1976) gives characters separating 5. nitidibaccatum from 5. sarrachoides Sendt.em.Bitter. All Landguard plants examined referable to 5. nitidibaccatum.

Tussilago farfara (Coltsfoot). The colony in M seems to have been ated by coast protection work.

Cynosurus cristatus (Crested Dog's-tail). Sown along the bank sep and F andfloweringprofusely in early summer. Plants on the southern side the bank appeared to die through lack of moisture in late 1983.

Bromus erectus (Upright Brome). Several plants were found in nort and northern F. These colonies appear to safeguard the continued existenc of the species on Landguard after destruction of the main area in G.

Voucher Specimens Material of the following species was sent to Mrs. E. M. Hyde at vario times during 1983 and early 1984: Epilobium tetragonum, Coria sativum, Polygonum aviculare S.S., P. arenastrum, Solan Anthemis cotula and Juncus ranarius.

References Clapham, A. R., Tutin, T. G. & Warburg, E. F. (1962). Flora ofthe B Isles. (Second Edition). Cambridge University Press.

Clapham, A. R., Tutin, T. G. & Warburg, E. F. (1981). Excursion F the British Isles. (Third Edition). Cambridge University Press.

Copping, A. (1983). Plant records from Landguard Common (1979-1982).

Trans. Suffolk Nat. Soc., 19,374.

Leslie, A. C. (1976). Solanum sarrachoides. B.S.B.I. News, A. Copping The Nook, The Green, Roydon, Diss, Norfolk IP22 3SD.

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