The distribution of Common Calamint and Lesser Calamint in Suffolk

THE DISTRIBUTION OF COMMON

CALAMINT

( I C A L A M I N T H A ASCENDENS JORD.) AND LESSER C A L A M I N T ( C A L A M I N T H A NEPETA (L.) SA VI) IN S U F F O L K E. M.

HYDE

In 1984 I published a list of all the Suffolk parishes in which Calamints had recently been recorded and asked members for details of any other sites known to them. Since then nine parishes (Redgrave, Shotley, Falkenham, Weybread, Dunwich, Westleton, Wrentham, Benacre and Higham, near Bury St. Edmunds) have been added for C. ascendens, making a total of thirty parishes. Two new sites at Long Melford and Cläre bring the total numberof parishes for C. nepeta to thirty-three. In addition, newcolonies, of which two await confirmation in 1987, have been found in known areas. For the sake of continuity I have used the 'old' name Calamintha ascendens throughout, rather than the now accepted C. sylvatica Bromf. ssp. ascendens (Jord.) P. W. Ball.

My aim in collecting these records was to compare the distribution of the two species in Suffolk, particularly vis-ä-vis the maps in the Atlas of the British Flora 1962, and to Supplement the account in Simpson s Flora of Suffolk, 1982. It is further hoped to produce, together with Dr. K. J. Adams, a country-wide map of the distribution of C. nepeta. As the work has progressed, it has become clear that more conservation measures are needed for C. ascendens, which is undoubtedly declining. I have already planted it in Woolverstone, replacing a lost site, on the STNC Roadside Nature Reserve.

Fortunately C. nepeta is already protected on at least two such Roadside Reserves.

Calamintha ascendens. As can be seen from the accompanying maps, Common Calamint is spread thinly over the County, though absent in the south-west. In England and Wales it is similarly thinly distributed as far north as Durham. In the Atlas it was under-recorded for Suffolk. The present survey has shown it to be present in twice as many 10km squares as recorded in the Atlas. Most noticeably, no records were given at all for the Shotley Peninsula, where there are at least seven sites. Fortunately, living on the Peninsula, my family and I have been able to fill in the gaps!

Colonies are generally small and decreasing. Of the four sites known in Chelmondiston in 1976 two have been reduced to a Single clump and one has disappeared. The typical Suffolk site is a sunny roadside bank, usually near houses. Most colonies suffer badly through verge-cutting. In July and August, when one would expect a good show of flowers, one frequently sees just a few wispy flower stalks, missed by the cutters, sticking out into the road. However, by September or October, after the last cut, they have produced a second crop of flowers and this is the best time to look for the plant. Whether any seed is produced from these late flowers is doubtful.

It is fortunate that Common Calamint grows also in eight Suffolk churchyards, or on walls or banks outside, and also on the Castle Mound at Framlingham. In such places it may be possible to ensure its survival.

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DISTRIBUTION OF COMMON CALAMINT AND L E S S E R CALAMINT IN SUFFOLK

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Suffolk Natural History, Vol. 23

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DISTRIBUTION OF COMMON CALAMINT AND LESSER CALAMINT IN SUFFOLK

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Calamintha nepeta. Lesser Calamint shows a very different distribution pattern. In Suffolk it appears to be restricted to the V a l l e y s of the R. Stour and its tributaries the Box and the Brett, and to one separate area east of Newmarket. The present distribution differs little from that in the Atlas. In Britain its chief strongholds are Suffolk, Essex and Cambridgeshire. In Suffolk, at least, it seems to be doing rather better than C. ascendens. Some colonies are very large. In and around Moulton, Assington, Stoke-byNayland and Hadleigh, for example, it is a conspicuous plant, forming large patches of pretty pinkish-lilac flowers. Like C. ascendens it likes sunny banks and verges, and occurs in or just outside churchyards in at least eleven parishes. There are also large colonies on railways banks at Brantham and Westley, and on the disused line at Hadleigh. Though verge-cutting must take its toll, it seems better able to withstand the onslaught than C. ascendens. It forms compact, ground-hugging, creeping patches with small leaves, which are less easily uprooted than the laxer non-creeping C. ascendens plants. In fact, so much of the latter species is torn out of the ground and so little of what remains is able to set seed that it is in danger of extinction on roadsides.

There are only three 10km squares in Suffolk in which both species of Calamint occur. TM13, my own Square, has Common Calamint in Stutton, Freston, Chelmondiston and (introduced) in Woolverstone, and Lesser Calamint in Brantham, Holbrook and Tattingstone. TL76 has Common Calamint in Higham, and Lesser Calamint in Moulton and Dalham. TL86 has a large colony of Common Calamint on the east side of Bury St. Edmunds and Lesser Calamint at Westley just outside Bury on the western side. These are the only known instances of an overlap of the two species. I cannot at the moment find any reason for this. Both plants like the same light soils and the same sunny sites. Perhaps a soil analysis at all the sites might provide a clue.

In the meantime I should be very pleased to hear of C. ascendens in the south-west of the County, and C. nepeta anywhere in the north or east.

I thank everyone who has sent in records in the last few years, and especially Mr. Milne-Redhead for his many records for C. nepeta. Details of all sites, with grid references and recorders' names, have been lodged at the Suffolk Biological Records Centre.

References Hyde, E. M. (1984). Calamints in Suffolk - a request. Trans. Suffolk Nat. Soc., 20,97.

Perring, F. H. & Walters, S. M. (Eds.) (1962). Atlas of the British Flora.

London.

Simpson, F. W. (1982). Simpsons Flora of Suffolk. Suffolk Naturalists' Society, Ipswich.

Enid M. Hyde, Parkside, Woolverstone, Ipswich IP9 1AR

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