111 ( N O T S O ) W E S T E R N G O R S E , ULEX GALLII
IN S U F F O L K
PETER LAWSON & MARTIN SANFORD In 1997 we decided to investigate the distribution of Western Gorse (LIlex gallii) in Suffolk. The species had been included in the 'Long list' of the UK Biodiversity Steering Group report (Anon, 1995) and we feit there was a need for better knowledge of its distribution. The British population is considercd of international importance as it represents between a quarter and half of the world population. The species is restricted to the westem edge of Europc where it is found in Portugal, Spain, France, Ireland and the U.K (see Fig. 3). There are several invertebrate species which are closely associated with, or dependant on, Gorse and it is quite possible that some of these may be specific to Western Gorse. The species is easy to find from late August to November when it is in fĂźll flower. It is usually a shorter plant with deeper yellow flowers than the Common Gorse (Ulex europaeus) which flowers mainly in the Spring (some bushes of U. europaeus Start flowering in late autumn). It is best to look for U. gallii in September before there is much overlap with europaeus. However, the two species can only be reliably distinguished by measuring the flower size and bracteole width (see Fig. 1). Once recognised, the Western Gorse has a distinetive 'jizz' which can be spotted even from a moving car - but you need to get your eye in first. There is a third British Ulex species - Dwarf Gorse, U. minor which is less easy to distinguish from U. gallii. It probably does not occur in Suffolk as a native, but for further details on identification see Praetor (1965), Bullock et al. (1998) and Kirchner & Bullock (1999). Humphries & Shaughnessy (1987) give a useful overview of Ulex taxonomy and biology as well as describing distribution, uses and folklore.
1 cm Figure 1. Flowers and calyces of Ulex. e: U europaeus, g: U. gallii, m: U. minor. Drawings by Hilli Thompson. Reprinted from Fig.. 418 of Clive Stacc's New Flora of the British Isles, 2nd ed. With the kind permission of the author and Cambridge University Press
Trans. Suffolk Nat. Soc. 35
(1999)
112
Suffolk Natural History, Vol. 35
Key characters: Calyx length U. europaeus 10-16 mm U. gallii 9 - 1 3 mm U. minor 5-9-5 mm
Bracteoles 1-8 - 4-5 x 1-5 - 4 mm, >2x as wide as pedicels <1-5 x 1 mm, <2x as wide as pedicels < 1 - 5 x 1 mm, <2x as wide as pcdicels
The Survey Although Simpson (1982) listed several 10 km squares for Western Gorse in Suffolk we had very few precise records and there had been confusion with other Ulex species which made past records difficult to interpret. It soon became clear that U. gallii was restricted to old established heaths with very acid soils, all in East Suffolk. Knowing this habitat preference made surveying somewhat easier as we could predict with a high degree of success which areas were likely to contain the plant. Preliminary searches were made from a car during August and September when U. gallii is in fĂźll flower and U. europaeus is generally (there are exceptions to this rule) not in flower. These were then followed up in more detail looking at all the 1 km squares in the area and checking identifications by close examination of the plants and, in some cases, measurements of flowers. Although we came across occasional plants which
6
7
8
9
0
1
2
3
4
5
Figure 2. Post-1997 1 km distribution of Ulex gallii in Suffolk. The shaded area shows the distribution of Typical Brown Sands (Soil Survey, 1983).
Trans. Suffolk Nat. Soc. 35 (1999)
WESTERN GORSE
113
appcarcd to bc hybrids between U. gallii and U. europaeus they were quitc scarcc and did not present major problems. By the end of 1998 we had found U. gallii in 84 1 km squares (see Fig. 2). From our knowledge of thc available suitable habitat in the County it probably occurs in at least another 10 1 km squares with the major gaps in our survey being around the southern end of Rendlesham Forest and in the Hollesley area where there are small areas of heathland which are not easily accessible. Düring the survey we also looked for Dwarf Gorse, Ulex minor which had been recorded in thc past from several East Suffolk parishes. We visited all sites of past records but were unablc to find any plants of this species except for some planted specimens by the roadside at Sutton Picnic Site (TM/306476) and in the flower beds at thc Warren Heath Sainsbury's outsidc Ipswich (TM/201423). Copping (1990) found several bushes flowering on 15 October 1988 which had been planted in front of the Customs & Excise building at Landguard Common, Felixstowe. Therc are two sheets labclled ' Ulex nanus' with specimens from Covehithc, Easton Bavents and Wrentham collected by W. M. Hind in the herbarium at Ipswich Museum; these are clearly specimens of U. gallii. It seems likely that other old records citcd by Hind (1889) are the result of confusion both with U. gallii and with weak plants of U. europaeus. Hind's herbarium also contains an interesting speeimen from Elveden which he had originally labclled 'nanus', but then annotated with 'probably a form of U. europaeus'. It is referred to in his Flora (1889) as 'form with shorter and weaker spines, thickly clothed with long whitish hairs, the calyces somewhat tomentose without black hairs'. It is a good example of the variablility shown by Ulex and the problems they present in identification. Examination of old records from Norfolk by J. H. Silverwood (Petch & Swann, 1968) showcd that all were in fact referable to U. gallii, the only record of U. minor for that county being an adventitious colony at Snetterton (TL/99). These findings present a striking contrast with Salisbury (1932) who, in describing thc 'Oceanic Component' of the East Anglian Flora suggested that Ulex nanus (= minor) 'is most abundant in the south-castern counties, whilst Ulex Gallii, though present in thc south-eastern counties, is only common in the west. In East Anglia U. nanus is occasional to frequent and is found both in thc western drier vice-counties as well as in thc eastern moister [!] vicecounties of Norfolk and Suffolk. Ulex Gallii, on the other hand, is confined to the eastern portions of these counties and is nowhere in the east of England more than rare.' He also suggested that 'U. Gallii is probably more tolerant of calcareous soils.' We suspect that Salisbury (and probably others) were relying on poorly identified records which in many cases were confusing U. minor with gallii. Distribution in the County Within the available suitable habitat U. gallii is quite frequent. Although therc are suitable soils beyond its ränge these areas have mainly been converted to arable farming and no longer contain heathland. Where large areas of heath have been used for forestry or military airfields thc species often survives in small numbers along ride edges and on roadside verges. •
Trans. Suffolk Nat. Soc. 35
(1999)
114
Suffolk Natural History, Vol. 35
Parishes Aldcburgh (Golf Course, North Warren) Aldringham (Walks & Common, Thorpeness Common) Beccles (an artificial bank on the bypass, could have been planted) Beiton Blaxhall (one large plant by the roadside in the middle of Blaxhall Common) Blythburgh Bradwell Brightwell (Heath) Butley Capel St Andrew (Tangham) Dun wich (Heath and Forest) Foxhall (Heath) Friston Fritton and St Olaves (Waveney Forest) Hollesley Hopton on Sea Ipswich (Rushmere Heath, Piper's Vale, Warren Heath) Lxiston (Sizewell) Martlesham (Heath) Nacton (Heath) Purdis Farm (Heath Rendlesham (Forest and around Woodbridge Airfield) Rushmere St Andrew (Bixley Heath) Snape (Black Heath Wood and Snape Warren) Southwold Sudbourne Sutton Tunstall (Common and Forest) Walberswick (Common and Tinker's Walks) Wenhaston-with-Mells Hamlet (Black Heath, Mill Heath, Church Common, Blowers Common and Bickers Heath) Westleton (Common and Heath) There are large populations on Rushmere Heath near Ipswich, Walberswick Common, Dunwich Heath (see Plate 11) and Westleton Common. At most other sites there are only small numbers. At Wenhaston the densities relative to U. europaeus are different on each of the heaths, perhaps reflecting differences in past management. Hybrids At several sites, we came across plants with characters intermediate between U. gallii and U. europaeus. These were easiest to spot when they had the habit of europaeus but the flower size and flowering time of gallii. There may well be other hybrids with different combinations of characters or, more significantly, different flowering times, which we did not recognise.
Trans. Suffolk Nat. Soc. 35 (1999)
WESTERN GORSE
115
Discussion There are two main areas of heathland in Suffolk; Breckland and the Sandlings. Whilst the flora of Breckland is well-known outside the County for its rarities there are very few plants which are found in the Sandlings, but not in the Breck. One such plant is the Westem Gorse, Ulex gallii. As the name suggests its main distribution in Britain (and Europe) is in the West (see Fig. 3). It is therefore rather odd that it should appear in good numbers in Suffolk in the driest part of the country. These populations are in fact the most easterly in the world. It has long been recognised that U. gallii has a preference for an 'Oceanic' climate. Humphries & Shaughnessy (1987) refer to it occurring 'where the climate is milder and more oceanic'. The species is classified as part of the 'Oceanic Temperate' element of British Flora by Preston & Hill (1997) and it is this preference for a climate in which winters are mild rather than a requirement for high rainfall which explains its distribution pattern both locally and within Britain. Similar patterns can be seen in other 'Oceanic' species such as Bell Heather, Erica cinerea (very often found growing with Western Gorse) and Climbing Corydalis, Ceratocapnos claviculata. Neither of these species is found in Breck heathland, where winters are much more severe and there can be frosts in any month of the year.
Figure 3. World distribution of Ulex gallii.
Trans. Suffolk Nat. Soc.
35(1999)
116
Suffolk Natural History,
Vol. 35
The Common Gorsc, Ulex europaeus is also an Occanic Tempcratc spccics, but it is lcss tcnder (though it can bc cut back or cven killed by hard frosts) and has sprcad from its natural ränge eastwards into Europe. It has also become naturalised in western North America and in the Southern Hemisphere (Preston & Hill, 1997). U. gallii seems to be a very good indicator of 'ancicnt' (good quality) heathland. It is often found with Erica cinerea and/or Calluna vulgaris. It is very closely linked with acid soils and this pattern is followed in Norfolk (Bull & Beckett, 1999). At all sites it is on Typical Brown Sands (Soil Survey of England and Wales, 1983), these are deep, well-drained sandy and coarsc loamy soils, they arc sometimes ferruginous and often very acid with a bleachcd subsurface horizon. The distribution pattern closely matches that of past heathland in the Sandlings as shown by Chadwick (1982). It does not occur on overgrown or ungrazed sites like Snape Church Common nor is it found in recently regenerated sites where Common Gorse has invaded such as Toby's Walks at Blythburgh. Acknowledgments We thank Mrs E. M. Hyde, Mrs J. Westcott and E. W. Patrick for supplying records and A. L. Bull and R. W. Ellis for information on Norfolk records. We thank the Soil Survey for permission to base the soil map on their information. References Anon, (1995). Biodiversity: the UK steering group report. - Volume 2: Action plans. HMSO, London. Bull, A. L. & Beckett, G. (1999). Flora of Norfolk. Norwich, G. Beckett. Bullock, J. M„ Connor, J., Carrington, S. & Edwards, R. J. (1998). Chromosome numbers and flower sizes of Ulex minor Roth, and Ulex gallii Planch. in Dorset. Watsonia, 22: 143-152. Chadwick, L. (1982). In search of heathland. Durham: Dobson Books Ltd. Copping, A. C. (1990). Plant records from Landguard Common, 1985-1988. Trans. Suffolk Nat. Soc.. 26: 64-75. Hind, W. M. (1889). The Flora of Suffolk. Gurney & Jackson: London. Humphries, C. J., & Shaughnessy, E. (1987). Gorse. Aylesbury: Shire Publications Ltd. Kirchner, F. & Bullock, J. M. (1999). Taxonomic Separation of Ulex minor Roth, and Ulex gallii Planch.: morphometrics and chromosomc counts. Watsonia, 22: 365-376. Perring, F. IL, & Walters, S. M. (1962). Atlas of the British flora. London: Thomas Nelson & Sons. Petch, C. P„ & Swann, E. L. (1968). Flora of Norfolk. Norwich: Jarrold & Sons Ltd. Preston, C. D„ & Hill, M. O. (1997). The gcographical relationships of British and Irish vascular plants. Bot. J. Linn. Soc., 124: 1-120. Praetor, M. C. F. (1994). Ulex minor in Stewart, A., Pearman, D. A., & Preston, C. D„ (eds.) (1994). Scarce plants in Britain. Peterborough: JNCC.
Trans. Suffolk Nat. Soc. 35
(1999)
WESTERN GORSE
117
Praetor, M. C. F. (1965). The distinguishing characters and geographical distributions of Ulex minor and Ulex gallii. Watsonia, 6: 177-187. Salisbury, E. J. (1932). The Easl Anglian Flora: a study in comparative plant geography. Transactions of the Norfolk and Norwich Naturalists' Society, 13: 191-263. Simpson, F. W. (1982) Simpson's Flora of Suffolk. Ipswich: Suffolk Naturalists' Society. Soil Survey of England and Wales (1983). Soils of England and Wales. Sheet 4 Eastern England. Southampton: Ordnance Survey. Stace, C. A. (1997). New Flora of the British Isles. 2nd ed. Cambridge: Cambridge University Press.
Peter Lawson 12 Park Lane Southwold Suffolk IP18 6HL
Clathrus
Martin Sanford SBRC Ipswich Museum High St Ipswich Suffolk IP1 3QH
ruber
This extraordinary 'cage' fungus, not unlike an overgrown practice golf ball in appearance, made only its third recorded appearance in Suffolk (v.c. 25) at the end of November 1998. By the time it was spotted in bare soil in a shrub border in urban Southwold, the lattice strueture had collapsed, leaving a number of strips of salmon pink tissue and the remains of the 'egg', from which it had emerged (see Plate 14). I had seen a partially intact, red-coloured fruiting body in the Isle of Wight in the mid-seventies (see photograph), so I recognised the Southwold remains, and my identification was confirmed when the spores were examined by Mrs. J. P. Ellis. The spores in this species occur in a sticky putrid smelling slime on the inside of the lattice strueture. No doubt the external colour looks like meat to insects, which are primarily attracted by the foul odour. As they investigate, they pick up spores and thus aid dispersal. The two previous county rccords were from Ufford and the Fiatford area during a fungal course in 1948. Peter Lawson, 12 Park Lane, Southwold, Suffolk IP18 6HL
Trans. Suffolk Nat. Soc. 35
(1999)
Plate 11: Western Gorse, Ulex gallii Planchon, abundant on Dunwich Heath, October 1998 (p. 114).
Plate 14: Fungus, Clathrus ruber Mich.: Pers., at Southwold, November 1998 (p. 117).