Effects of land management on the location and status of populations of Spiranthes romanzoffiana in Scotland: a desk review and evaluation of the available evidence

Dr. Scott McG. Wilson MICFor Consultant Forester and Forest Ecologist

Report to Plantlife Scotland – June 2005

Executive Summary

Irish lady’s-tresses (Spiranthes romanzoffiana) is one of the rarest members of the Orchidaceae in Europe, occurring only at scattered locations on the western seaboards of Scotland and Ireland, and at one location in south-western England. Otherwise the species occurs widely in many parts of North America in wetland habitats. The species was first recorded in Ireland in 1810 and in Scotland in 1921, with an accumulation of records in both countries until the 1990’s. Survey work conducted in both Ireland and Scotland during the past 10 years has indicated that the species is now absent from many sites at which it has previously been recorded. For that reason it is the subject of a Species Action Plan in both the UK and Ireland and has been included within Plantlife Scotland’s “Back from the Brink” recovery programme.

In Scotland Spiranthes romanzoffiana occurs mainly on a range of wet pasture and wetland sites on lands subject to extensive pastoral agriculture in the crofting districts. A variety of vegetational contexts are involved, including Molinia grassland, mesotrophic mires and Juncus pastures. A set of broad land management prescriptions for the species has been developed based on empirical observation, including seasonal inundation, ground disturbance by livestock, extensive winter grazing by cattle and restriction of summer grazing (especially by sheep). However the relationship between these practices and Spiranthes romanzoffiana longevity is rather tentative.

The current study sought to explore the possibility that historical land management information for sites where Spiranthes romanzoffiana has persisted might shed light on the optimum land management practices to be recommended under future agri- environmental schemes. A range of sources and techniques were employed in the work, including discussions with relevant specialists, incidental site visits and review of published and unpublished documents held by libraries and by the National Archives of Scotland, Edinburgh. Studies using land management records and estate archives have proved valuable in illuminating past woodland management in Scotland, but their application to other habitats has been much more limited to date.

This work produced some further evidence in support of the existing management prescriptions for Spiranthes romanzoffiana based on recent observations. Historical records provided a chronological overview of changes in land management practices in the crofting areas concerned over the past two centuries, including a reduction in arable and potato cultivation, an increase in sheep stocking at the expense of cattle and a reversion of considerable amounts of former agricultural land to semi-natural vegetation under extensive grazing systems. While this historical information could at times be given a local flavour, there was insufficient evidence available to inform detailed ecological reconstruction of individual sites with Spiranthes romanzoffiana. Similarly, it was found to be impractical to relate the present status of Spiranthes romanzoffiana populations to land management prior to that of recent years, as data of sufficient spatial resolution do not exist. While the desk review may not be exhaustive it is not indicated that extension of the work using similar methods would be useful.

Future work on Spiranthes romanzoffiana in Scotland should employ field studies, preferably under controlled experimental conditions, to investigate the physiological and reproductive responses of this species to different patterns of herbivory. Further work on the reproductive system and life-cycle of the species is also recommended. Contents

1 Introduction ...... 2 2 Objectives ...... 4 3 Methods ...... 5 4 Results ...... 9 5 Conclusions...... 13 6 Recommendations for further work ...... 14 7 References...... 15 8 Acknowledgements ...... 17

Front cover image © Andrew Scobie Back cover image © D. Long / Plantlife

1 Introduction

1.1 Distribution

Spiranthes romanzoffiana presents a conundrum in that its major ecological distribution is in North America, with a small number of European populations along the western seaboards of Scotland and Ireland. This is termed an “amphi-Atlantic” distribution and is displayed by a number of other scarce plants in the British Isles. While a number of hypotheses have been advanced for this distribution pattern, including fragmentation by continental drift and introduction to Europe by animal or human vectors, the most likely appears to be wind transport of the very light seeds. Although the species was not recorded in Ireland until 1810 or Scotland until 1921, it is considered to be native in both territories. Its occurrence prior to these dates is unknown – it may have been present and gone unrecorded or it may have been absent.

Early records in Scotland included the Isle of Coll (1921) and the Isle of Colonsay (1931). These were added to in the post-war years by occasional records on the Isles of Colonsay, Coll, Tiree, Mull, Barra and Vatersay and on the mainland in Ardnamurchan, Morvern and Kintyre. A total of some 70 locations were recorded. In the mid-1990’s a more systematic survey was commissioned by Scottish Natural Heritage which relocated the species at only some 11 of these sites and at a further seven sites where the species had not been recorded before, although in nearby areas. A similar reduction in the number of recorded sites has been observed in Ireland. This evidence prompted the preparation of Species Action Plans (SAPs) for Spiranthes romanzoffiana in both the United Kingdom and the Republic of Ireland. Plantlife Scotland are the lead partner for Spiranthes romanzoffiana in the UK, carrying out a programme of work under a funding arrangement with Scottish Natural Heritage.

1.2 Ecological site requirements

The habitat requirements of Spiranthes romanzoffiana in North America are understood to be natural wetlands such as muskeg forest and beaver meadows, which will be subject to grazing by natural herbivore species such as elk and deer. The sites where the species has been recorded in Europe display a wide variety of conditions within a broadly wetland habitat category. These include lake margins, peat bogs, rush pastures and wet grasslands dominated by Molinia caerulea. Spiranthes romanzoffiana appears to require good top-lighting and at least moderate soil fertility. A preference for seasonal inundation has been suggested, but the species does not favour permanently aquatic conditions. The topographical position of most populations in Scotland is transitional between coastal “machair” ecosystems with a shell-sand influence and largely ombrotrophic blanket mire systems further inland. Most such sites have in the past been subject to some form of agricultural system.

2 1.3 Reproduction and life-cycle

Spiranthes romanzoffiana has not been observed to set seed in Scotland and attempts to collect viable seed have invariably failed. It is assumed to reproduce entirely by asexual means, although the mechanism of spread has not been established as yet. Some form of physical disruption of the roots of the plant may be essential in permitting vegetative spread and it is proposed that cattle trampling can achieve this. Recent genetic studies have suggested that the populations in Scotland may be able to achieve some level of out-crossing, or have done so in the past by unknown means.

Spiranthes romanzoffiana plants go through a complex life-cycle of flowering spikes, vegetative florets and “underground” phases. In the latter case trophic support by a fungal associate is likely to be involved, and this may also serve to synchronise the physiology of plants forming a single site population. In the “underground” phase the plant cannot be recorded by botanical survey, and this may lead to previously recorded populations failing to be relocated in a particular year. This has potentially serious consequences for the reliability of the hypothesis that the species is declining in Scotland and Ireland. It may indeed remain heavily under-recorded. Work on Barra has suggested that continued survey and plant marking over a period of several years may be required if population status is to be assessed with confidence. Flowering spikes are produced in the summer season and that is the easiest time to conduct surveys. Herbivory in summer by ungulates and slugs may remove flowering spikes.

1.4 Land management prescriptions

Current conservation management for rare plant species is based upon the development of “management prescriptions” which can be incentivised under agri- environment schemes. Fully reliable prescriptions are only possible where the autecology of a species is fully understood, and this is certainly not the case for Spiranthes romanzoffiana at the present time. However a suite of tentative land management prescriptions for Spiranthes romanzoffiana have been developed from empirical observation over the past half-century and these remain the basis of current management advice for this species. These prescriptions can be summarised as:-

• Avoidance of artificial site improvement (drainage or fertilization); • Retention of seasonal inundation (e.g. “winter lakes”) where site natural; • Winter grazing by cattle, with localized poaching allowed to occur; • Avoidance of summer grazing (especially intensive sheep grazing); • An element of irregularity in grazing patterns over a number of years.

Many of the largest and most persistent populations of Spiranthes romanzoffiana are observed to occur at locations where grazing patterns are irregular and sporadic with occasional poaching and disturbance and in some cases seasonal inundation. It is suggested that optimally, control of potentially competitive vegetation by winter grazing or inundation is combined with occasional ground disturbance by trampling to encourage vegetative spread of Spiranthes romanzoffiana. Intensive summer grazing results in a loss of biomass of flowering spikes and is likely to be adverse, although populations subject to year-round heavy grazing have also been observed to persist.

3 An early observation that Spiranthes romanzoffiana was closely associated with Molinia caerulea pasture developed over old “lazy-beds” has not been found to be an obligate relationship. Such sites display the set of ecological conditions required by Spiranthes romanzoffiana, but this is also true of a number of other wetland contexts.

A listing of the scientific references from which the above information is summarised is provided at the end of this report. The previous work of Gulliver et al. on Colonsay, Robarts on Barra and Henderson on Coll are of particular relevance.

2 Objectives

The current project sought, by means of a short desk review over twelve working days, to evaluate the potential importance of past land use as an explanatory variable for current Spiranthes romanzoffiana population status and thereby to help revise and refine the existing tentative land management prescriptions described above.

Within this context, the specific aspirations of the current project were to:-

• Identify types of historical land management formerly practised at selected present Spiranthes romanzoffiana population sites, including both arable and pastoral systems, having regard to their relative extent and timing.

• Assess the impacts of these different historical land management types on past habitat structure and suitability through the use of proxy vegetation data.

• Evaluate information of the past status of Spiranthes romanzoffiana populations with reference to periods when different land management systems were applied.

• Explore relationships between past land management systems and present status of Spiranthes romanzoffiana populations.

• Analyse trends in the ecological status of existing Spiranthes romanzoffiana populations in relation to land management systems.

It was expected that the following aspects of historical land management would be of particular interest and concern in relation to the status of existing Spiranthes romanzoffiana populations:-

• Changing use of croft in-bye land from cultivation to pasture;

• Change in the livestock ratio from cattle towards reliance on sheep stocking;

• Cessation of hay making and fodder production on in-bye land;

• Regular use of routes by cattle (formal or informal) and associated trampling;

It was recognised from the outset that the level of detail of information produced by the study would prove highly dependent on the quality of archival records available in relation to historical land management in the districts involved. While Scotland as a whole has historical land management archives which are comparatively well

4 developed, those areas of the country where existing Spiranthes romanzoffiana populations occur are among the most poorly recorded for cultural-historical reasons. Most previous land use history analysis in the crofting areas has operated at the locality or sub-regional level and has often been based on anecdotal secondary sources. Use of primary sources of information at the site level has generally been restricted to better recorded parts of Scotland and to woodland habitats which were often recorded by exception. As the present study was limited to twelve days of desk review work it was anticipated that the use of primary archival sources would need to be selective, and might need to identify additional material that could be explored in any future study.

3 Methods

The present study consisted of a period of twelve days of desk review work conducted between April and June 2005, augmented by informal visits to Spiranthes romanzoffiana population centres on the Isles of Mull and Colonsay in Argyll. The desk investigation was focussed on five major Scottish population centres for Spiranthes romanzoffiana on the Isles of Barra, Coll, Colonsay and Mull and on the mainland peninsula of Morvern – all areas formerly regarded as being in Argyll.

The desk review work consisted of five main phases:-

1. Consultation of existing scientific experts on Spiranthes romanzoffiana. 2. Review of the scientific literature on Spiranthes romanzoffiana. 3. Identification and review of published literature relevant to land-use history in the crofting districts concerned. 4. Identification and review of unpublished documentary sources relevant to land- use history in the crofting districts concerned. 5. Collation of evidence collected, analysis, evaluation and reporting.

The following detailed methods of research were employed in this study:-

3.1 Consultation of existing scientific experts on Spiranthes romanzoffiana

Discussions and correspondence with a number of individual botanical and ecological specialists having previously studied Spiranthes romanzoffiana were conducted. These included Edinburgh-based organisational specialists from Scottish Natural Heritage, RSPB Scotland and the Royal Botanic Gardens, Edinburgh. However locally-based individuals with a detailed knowledge of Spiranthes romanzoffiana populations were also contacted and were able to provide substantial insights into past and present land management at the highlighted sites, based on personal observations and discussions with current land managers. This was of particular value as it was not practical for the author to visit all of the localities concerned within the scope of this short study. Information was also sought from locally-based Scottish Natural Heritage staff, but no additional information became available from that source within the timescale of the study.

5 3.2 Review of the scientific literature on Spiranthes romanzoffiana in Britain and Ireland

A comprehensive review of the published (and “in press”) scientific literature on the ecology of Spiranthes romanzoffiana in Britain and Ireland was conducted to develop an understanding of what is already known about the species and its requirements. The outcomes of this work are summarised in the Introduction and a full bibliography is provided at the conclusion of this report. The UKBAP and All Ireland Species Action Plans for Spiranthes romanzoffiana were also reviewed. The Spiranthes romanzoffiana populations on Barra, Coll and Colonsay have all been the subject of specific scientific articles based on local ecological investigations over the past decade, which have examined the effects of different grazing systems and vegetation structure upon the success and longevity of Spiranthes romanzoffiana populations.

3.3 Review of published literature sources dealing with historical land management

This phase of the desk review work adopted 1800 as a starting point. This date was selected as Spiranthes romanzoffiana was discovered for the first time in the British Isles in 1810 (although not in Scotland until 1921). Also, before approximately that date (perhaps more appropriately 1750) there are very few underlying documentary historical sources relating to land management in Highland Scotland and the published literature is therefore based primarily on modern archaeological studies.

From the late eighteenth century onwards there are a variety of published sources which provide information on land use in the West Highlands. These can be subdivided into (a) those which are based on personal observation by the author, (b) those which are reliant upon summary and representation of material in previously published or primary sources, including oral history and (c) those which report the work of systematic study of current land management in the areas concerned.

The types of published historical sources reviewed are discussed below:-

General Accounts

From the late eighteenth to the mid twentieth centuries there was a genre of “general library accounts” of various West Highland districts, often prepared by the proprietor of a land area or wealthy individuals visiting his house. These were inspired by the works of Pennant and Johnson & Boswell in the period following the final Jacobite rebellion of 1745. The publication by Loder (1935) regarding the Isle of Colonsay falls into this tradition. These sources often rely upon a mix of amateur observation and local oral tradition, reflecting the interests of the author. On occasion they do comment on land management – either to praise improvements introduced by the proprietor or to bemoan the state of poverty and backwardness of the local populace. While the main types of land management may be discussed, the resolution of the information is usually at the locality/ parish level as opposed to the site scale. More recent examples of this type of publication are aimed primarily at the motor tourist and contain even less detailed information on land management.

6 Local Histories

From the 1930’s onwards there has been an increased interest in scholarly local historical research in the West Highlands, leading to publications based on review of the available oral and written historical evidence for a locality. The inspiration for this genre of text was probably the early work of John Lorne Campbell and Margaret Fay Shaw in the 1930’s on Barra, leading to the publication of the “Book of Barra”. More recent examples include Currie (2000) regarding Mull. Most such texts deal in some detail with the traumatic period of the Highland Clearances in the early-mid nineteenth century and the subsequent period of crofting reform and agitation up to and including the First World War. A major primary source for such publications has been the report of the Napier Commission of the 1880’s, which was tasked to investigate hardship in the crofting districts – effectively an earlier version of the West Highland Survey, but employing more anecdotal methods. These local histories frequently deal with agricultural practices in a locality – charting major trends such as the decline of the traditional Highland township with its “runrig” common fields, the increasing use of kelp for fertilization, the cultivation of the potato and its demise in the famine of the 1840’s and the rise in numbers of sheep being kept by proprietors at the expense of tenants’ cattle. However these trends were reflected throughout the West Highlands between 1800 and 1950 and most local histories do not provide information which has sufficient spatial or temporal resolution to track specific changes that could have affected Spiranthes romanzoffiana populations (had these been present).

The Old, New and Third Statistical Accounts of Scotland

These were compiled by returns from Parish ministers in the 1790’s, 1840’s and 1950’s respectively (with some official assistance in the latter case). They improve upon the “general account of conditions” sources in being systematic first hand accounts, but again they only record general observations as to agricultural circumstances in each reporting Parish as a whole. The level of detail and emphasis of each Parish report depends strongly on the personal interests of the incumbent minister, particularly in the Old and New Accounts. Entries for relevant parishes were reviewed as potential sources in this work, but none contained agricultural or botanical information of any resolution.

The West Highland Survey

This was a central government-sponsored survey of economic, social and environmental conditions in the West Highlands undertaken in the immediate aftermath of the Second World War under the leadership of Frank Fraser- Darling. To some extent it represents an attempt to develop further the basic modus operandi of the Statistical Accounts mentioned above, but employing travelling recorders with a greater level of land management expertise than the Parish ministers would normally possess. The objective was to develop policy proposals for alleviation of economic hardship in the West Highlands and to promote agricultural and economic development. As a result it sought to “take stock” of agricultural conditions at that time as a “baseline”. The published volume includes a detailed report on the Isle of Coll which is of some relevance to the current work. Detailed “snapshot” agricultural information was collected at the level of the crofting township in many other areas, but the published report contains only data aggregated to the Parish level for reasons of publication convenience. Original data was encoded on early computer punch-cards which are now lodged at the National Archive of Scotland in Edinburgh. Although the

7 relevant computer equipment to read these no longer exists, the cards could possibly be reinterpreted manually, but this task was not pursued within this study as it would be likely to be very time consuming. No comparably detailed survey of West Highland agricultural conditions has been published since the time of the West Highland Survey report in 1955.

Agricultural Census and IACS Returns.

Farmers have been required since the mid 19th century to submit annual census returns to the Department of Agriculture for Scotland (and its successors) every 4th June. These returns report acreages, production levels and livestock holdings in some detail, although without mapping for most of this period. More recently these have been superseded by IACS (Integrated Administration and Control System) form returns under the Common Agricultural Policy. However information from these returns is only ever published aggregated to the Parish level (more lately County level) and returns from individual agricultural holdings were not retained from the earlier surveys and are regarded as client confidential for more recent information. Field scale information was not collected at all until more recent years when better digital mapping and surveying techniques became available for use. Sample returns from Parishes of interest were evaluated as potential sources, using microfilm resources at the National Archives of Scotland. However the large size of West Highland parishes means that the information cannot be used effectively to assess agricultural practices influencing particular sites. Fraser-Darling reached the same conclusion, leading to the West Highland Survey commissioning original data collection and recording as stated above.

Published Maps

First edition Ordnance Survey 6-inch maps for the selected Spiranthes romanzoffiana population site areas were examined, but do not represent land management information for individual agricultural fields. Land use maps are available for Scotland from the 1930’s onwards but are at too small a scale for the purpose at hand and only represent broad categories such as rough grazing. Unpublished estate maps referred to are dealt with in the following section.

3.4 Review of unpublished documentary sources dealing with historical land management

Experience gained in the course of research in recent years on woodland management history in Scotland has suggested that use of unpublished primary historical documents generally known as “estate papers” can be effective in researching historical land use. Much such work has been reported in the proceedings of the Scottish Woodland History Discussion Group and in historical works by Smout. However there is much less experience of using this approach for non-woodland habitats – woodlands have generally been much better recorded as an exception to the rule of upland agriculture which often engendered legal correspondence with tenants and specific plans of management at the instigation of improving landlords. Also the work to date even on woodlands has focussed on those areas of Scotland such as Perthshire, Badenoch, Aberdeenshire and the Borders which developed a literary tradition in English at an earlier date and had better communications with Edinburgh. The use of this approach to investigate crofting land

8 use history at the Spiranthes romanzoffiana sites would be expected to be less productive as the localities are in areas of the country with a much poorer legacy of written records and the forms of land management being studied are the rule rather than the exception.

Work of this type is made feasible by the fact that many sets of private estate papers have been deposited at the National Archives of Scotland in Edinburgh where their contents are already indexed in great detail and can be searched for on-line. Use of these facilities highlighted a rather small number of papers, mainly estate maps, relating to areas containing the Spiranthes romanzoffiana sites under investigation. These were ordered in from the NAS depository and examined, but did not contain very much information that would add greatly to that collated from other sources.

Use of un-indexed estate papers in private collections is a much more demanding task and could not be attempted within the time-frame of a short desk review project.

3.5 Field visits to selected Spiranthes romanzoffiana population localities

The opportunity was taken to make brief reconnaissance visits to those localities on Colonsay and Mull where populations of Spiranthes romanzoffiana have been recorded in recent years. Field positions supplied by Plantlife Scotland were used to orientate the visits using a GPS handset. The objective was not to locate or survey the plants themselves, but rather to familiarise myself with the range of habitats and land-use contexts applying at the sites involved. Sample site photographs were taken.

4 Results

The results available from this desk review work essentially fall into three parts:-

• A reconfirmation of the relevance of existing land management guidance in relation to the conservation of populations of Spiranthes romanzoffiana; • A chronology of changes in land management practices taking place between 1800 and 2005 in the West Highland crofting districts as a whole; • An attempt to give some tentative indications as to how these general trends in land management might have specifically affected Spiranthes romanzoffiana localities on Colonsay, Coll, Barra, Mull and Morvern.

It will be recognised from the appraisal of documentary sources given above that there is insufficient information to inform a detailed analysis of past land use patterns at the individual Spiranthes romanzoffiana populations sites or to proceed to relate that analysis to proxy vegetation data or current Spiranthes romanzoffiana status.

9 4.1 Current land management and Spiranthes romanzoffiana population status

Although there is some inconsistency between the views of recent scientific authors on Spiranthes romanzoffiana, there seems to be sufficient evidence to support the following recommendations in terms of land management for its conservation:

i. Land management should not be altered where it is currently consistent with healthy populations of Spiranthes romanzoffiana. Where patterns of land management are erratic and difficult to describe it may be necessary to define acceptable limits to change in proxy vegetation parameters to ensure that conditions remain comparable. Optimal patterns of grazing and disturbance are very difficult to define given the limited level of understanding of the autecology of the species and evidence of existing Spiranthes romanzoffiana population success is by far the best indicator.

ii. No artificial improvement of population sites by installation of field drains or application of artificial fertilizers should be undertaken.

iii. Where seasonal inundation currently occurs at sites carrying Spiranthes romanzoffiana populations, no action should be taken which alters this.

iv. Grazing by cattle outside the Spiranthes romanzoffiana flowering season should be continued and encouraged. The intensity of this grazing should be sufficient to restrict the growth of competitive species such as Juncus which can tend to shade out Spiranthes romanzoffiana. A certain amount of local ground disturbance by cattle trampling should be tolerated, as this appears to be associated with Spiranthes romanzoffiana regeneration and spread, although the mechanisms by which this effect occurs are unknown.

v. Grazing during the Spiranthes romanzoffiana flowering season should be discouraged – especially heavy grazing by sheep and lagomorphs. Such grazing removes the possibility of sexual reproduction of Spiranthes romanzoffiana and may restrict vegetative perpetuation by excessive removal of biomass. It is recognised that work on Colonsay has suggested that Spiranthes romanzoffiana can sustain intensive summer grazing at least in the short term, but it remains likely that it will be detrimental in the longer term, especially if intensive and prolonged. Where some summer grazing currently occurs at sites with successful Spiranthes romanzoffiana populations, this should be sustained at the current level and pattern.

vi. Consideration should be given to lagomorph control at sites where there is evidence that these animals effect significant herbivory on Spiranthes romanzoffiana populations. This evidence should be the result of systematic monitoring of the populations of rabbits and of Spiranthes. vii. Consideration should be given to slug control at sites where there is evidence that these animals effect significant herbivory on Spiranthes romanzoffiana populations. This evidence should be the result of systematic monitoring of the populations of slugs and of Spiranthes. viii. Monitoring of populations of Spiranthes romanzoffiana must be conducted over a cycle of several years to allow for the effects of the “underground phase” on the reliability of estimates of numbers of plants. Locational tagging of individual

10 plants when they emerge is the optimal approach. Protection of individual Spiranthes romanzoffiana plants from grazing should be avoided as it may engender excessive vegetation competition.

4.2 Historical trends in land management in the West Highland crofting districts

• Until the early nineteenth century a traditional pattern of Highland agricultural townships was maintained with unfenced cultivated “in-bye” land on better drained ground being managed for grain and vegetable crops as well as winter livestock fodder. This was apportioned between families using a variety of systems, including that known as “runrig”. Livestock were a mixture of cattle, goats, horses and sheep, with cattle being primarily for export sale and sheep of small hardy breeds for local subsistence consumption. Livestock were summered on rough upland pastures with a shieling system of husbandry where younger family members camped out with the stock to ensure that they used the forage area efficiently and did not return to the in-bye land. In winter livestock were either housed or more normally allowed to graze off the in-bye land where supplementary fodder was supplied from a late summer hay cut.

• With increasing population pressure in the early to mid nineteenth century some areas with progressive landowners saw attempts to “improve” the agricultural systems applied by bringing more land into cultivation and introducing lowland- inspired crop rotation systems on the arable land. Kelp was used as an additional source of fertilization for the in-bye land to supplement the dunging of cattle during the winter months. This allowed greater areas of land to be productively cultivated. Some areas also saw an increase in rabbit populations as an alternative food source. However, other areas saw marginal land brought into cultivation by use of the “lazy-bed” system which employs furrowing to raise part of the area above a water table which is permanently close to the level soil surface. There was increasing reliance upon the introduced potato as a food crop which was more amenable to the lazy-bed system than would be most arable crops.

• The mid nineteenth century saw the initiation of a number of major changes to the West Highland agricultural situation which were to play out over the following decades:-

• The failure of the potato crop in the late 1840’s due to the outbreaks of Phytophthora fungal blight;

• A decline in the value of store cattle as an export crop due to the introduction of refrigerated transportation from the USA, Canada, Argentina and Australia;

• Introduction of intensive sheep husbandry using larger breeds by some proprietors in response to demand for wool supplies;

• Large-scale emigration of parts of the population to North America and associated abandonment of cultivated lands;

• Confinement of parts of the population to smaller croft holdings on more marginal land areas, often nearer to the coast.

11

These processes proceeded at different rates and intensities in each locality within the West Highlands. Some areas, especially on the Islands, saw a continuation of previous “township” system at a smaller holding scale, with crofters retaining a mixed agriculture of cattle, sheep and arable land. Other areas saw a conversion to a sheep ranching economy with cattle and arable cultivation largely discontinued – this applied especially to some of the “straths” on the mainland of the West Highlands from which emigration of the farming population had been at its most pronounced.

• The early twentieth century saw improved communications by sea, rail and road and a continued reduction in the numbers of the human population. Arable cropping continued to diminish as an element of the crofting economy as food products could be bought in at more reasonable costs. In-bye land was increasingly used for the production of winter fodder allowing more livestock to be kept. In most areas cattle numbers declined in favour of sheep, which were now more usually exported by sea/rail.

• During the mid and late twentieth century a similar process took place by which the production of hay for winter fodder from the in-bye land has been abandoned in favour of fodder bought in from east Highland areas. This has allowed the in-bye land to be opened to summer sheep grazing, producing a short-cropped grass sward which is frequently semi-improved. Agricultural economics and a reduction in available on-farm labour have conspired to disadvantage cattle in favour of an extensive sheep system. Many crofting areas now have much less distinction between in-bye and hill grazing land, with only gentle ridges showing areas of former arable.

• Recent years have seen some reduction in sheep stocking in response to low product prices and a resulting tendency of former pastures to revert to semi- natural vegetation assemblages with abandonment of drainage and fertilization activities. The sward usually becomes out grown with coarse species such as Juncus and thus probably less suitable for Spiranthes romanzoffiana, as well as many other shade intolerant plant species. Agri-environmental schemes have sought to address these changes by offering incentives to reintroduce hay cropping and cattle rearing in some areas.

4.3 Factors specific to the localities of the selected Spiranthes romanzoffiana populations

Within the range of agricultural conditions described above, those areas with major Spiranthes romanzoffiana populations tend to be characterised by a retention of cattle grazing as an element of agricultural practice, with related diversity in sward height. Although some of the populations are found on areas that may formerly have been cultivated under the lazy-bed system, this appears to relate to only a small proportion. The following comments can be made about each Spiranthes romanzoffiana population locality (details of locations are tabulated in the Appendix as advised):-

Coll

The populations on Coll are found on sites with complex grazing regimes. The largest population at Arileod is in a field with an erratic recent history of sheep

12 and cattle grazing, while other populations are on rough hill grazings. Between the 1750’s and 1950’s Coll had an agricultural economy based partly on dairy farming by settlers from Ayrshire. Sheep numbers have increased at the expense of cattle in more recent times, but both types of stock are still kept. The RSPB are currently incentivising management regimes for the Spiranthes romanzoffiana populations on Coll consistent with those recommended above.

Colonsay

The populations on Colonsay are found on sites with a wide range of grazing regimes and associated vegetation assemblages. These include rough grazing and water meadows, for example. Both cattle and sheep are present at many of the sites, with some having a summer grazing break and others not. Some of the sites have a close-cropped grass sward due to sheep grazing. Colonsay was one of the localities that saw notable improvement in its agricultural regime in the early nineteenth century, with up to one-third of the land arable. Maps of that time suggest that at least some of the Spiranthes sites may have been cultivated. Rabbits became common from this time onwards on the island. The proportion of cultivated land has since declined to a minimal area, but some fields are used for more intensive cattle rearing with a semi-improved sward.

Barra

The large population on Barra is in an area of croft grazing land which still has cattle and where a summer grazing break is regularly maintained until today.

Mull

The population on Mull (Morinish, by Calgary) is on a partially drained peat bog, apparently subject to only light grazing, thought likely to be occasional.

Morvern

The population near Drimnin, Morvern is reported to be on ordinary rough hill grazing land, although early nineteenth century estate maps show cultivation in or close to the area, now long since abandoned following the clearances.

5 Conclusions

The principal conclusions that can be drawn from this work are:-

a. The autecological site requirements and reproductive systems of Spiranthes romanzoffiana in Scotland remain relatively poorly understood which makes the specification of appropriate land management prescriptions for this species problematic.

b. Further field research trials are necessary to investigate various aspects of the biology of this species with a view to informing refined land management prescriptions for its conservation. These trials need to be conducted over a number of years and to adopt intensive monitoring methods if they are to be effective in addressing these information needs.

13 c. An interim set of land management prescriptions has been evolved from empirical experience, which involves winter grazing by cattle, ground disturbance by cattle trampling and restriction of summer grazing. While the causal relationships between these practices and the longevity of Spiranthes romanzoffiana populations are not well understood, they represent the best available guidance for land managers seeking to conserve this species and they should be promoted and incentivised.

d. Review of historical sources suggests that the proportion of land in the crofting areas subject to land management meeting these interim prescriptions for Spiranthes romanzoffiana has been in apparent decline since the early twentieth century due to reductions in cattle numbers and an increase in year- round grazing by sheep. A new challenge may now be emerging as sheep numbers decline and land becomes occupied by rank vegetation types that will disadvantage Spiranthes romanzoffiana.

e. The methods of historical land use management analysis are not able to track the status of Spiranthes romanzoffiana populations over time in relation to changing land management at the sites due to an absolute lack of agricultural and botanical records of sufficient resolution or consistency. It is considered unlikely that further work of this type would be fruitful.

f. Many of the areas where healthy populations of Spiranthes romanzoffiana are currently found are managed to some degree in accordance with these interim prescriptions as described above, although other sites are in apparently less favourable conservation status due to under/ over grazing.

6 Recommendations for further work

In relation to Spiranthes romanzoffiana, Plantlife Scotland should:-

• Promote improved survey and monitoring of Spiranthes romanzoffiana populations in Scotland in support of the Species Action Plan. Survey work should seek to create a more consistent national register of populations, including information as to location, land use practices, number of plants and physiological status. A selection of populations representing different habitat types and applied grazing regimes should be intensively monitored over a ten year period with all emergent plants tag-marked in each year’s flowering season. The objective of the monitoring is to clarify the vegetative cycle of Spiranthes romanzoffiana and to evaluate the effects of different land management systems on population status.

• Promote work to investigate the reproductive biology of Spiranthes romanzoffiana in Scotland in detail, if possible arriving at an efficient and reliable laboratory procedure for vegetative propagation in this species.

• Promote research using vegetative propagated reproductive material of Spiranthes romanzoffiana in common garden experiments where different herbivory and disturbance regimes could be simulated under controlled and quantifiable conditions, with a view to producing refined grazing management guidelines for the species in the field based on hard evidence.

14 • Promote increased scientific discourse and collaboration with botanists and biologists in North America who may be conducting work on this species or who may wish to participate in collaborative work along these lines.

7 References

Allan, B. and Woods, P. (1993) Wild Orchids of Scotland. Edinburgh: HMSO.

Bowler, J. (2003) Irish lady’s-tresses (Spiranthes romanzoffiana) discovered on the Isle of Tiree, Argyll. BSBI News – the newsletter of the Botanical Society of the British Isles, 92, 25-26.

Campbell, J.L. (1936) The Book of Barra. London: Routledge.

Catling, P.M. (1990) Biology of the North American representatives of the Subfamily Spiranthoideae. In: North American Native Terrestrial Orchid Propagation and Production. Ed: Sawyers, C.E. Brandywine Conservancy, Chadds Ford, Pennsylvania.

Currie, J. (2000) Mull: The Island and its People. Edinburgh: Birlinn.

Ferreira, R.E.C. (1978) Spiranthes romanzoffiana sites on Coll. Peterborough: Nature Conservancy Council.

Forrest, A.D., Hollingsworth, M.L., Hollingsworth, P.M., Sydes, C. and Bateman, R.M. (2004) Population genetic structure in European populations of Spiranthes romanzoffiana set in the context of other genetic studies on orchids. Heredity, 92, 218-227.

Fraser Darling, F. (1955) West Highland Survey: An Essay in Human Ecology. Oxford: Oxford University Press.

Gaskell, P. (1996) Morvern Transformed: A Highland Parish in the Nineteenth Century. Cambridge: Cambridge University Press.

Gilbertson, D., Kent, M. and Grattan, J. (1996) The Outer Hebrides: The Last 14,000 Years. Sheffield: Sheffield Academic Press.

Gulliver, R.L. (1996) The status of Spiranthes romanzoffiana Cham. (Orchidaceae) Irish lady’s-tresses, on Colonsay (vc102) in 1995, with special reference to associated plant communities. Watsonia, 21, 202-204.

Gulliver, R.L. (1997) Irish lady’s-tresses (Spiranthes romanzoffiana), on Colonsay (vc102). Glasgow Naturalist, 23(2), 55-56.

Gulliver, R.L., Keirnen, M., Gulliver, M. and Sydes, C. (2000) Observations on Irish lady’s-tresses (Spiranthes romanzoffiana), on Colonsay (vc102). Glasgow Naturalist, 23(5), 9-12.

Gulliver, R.L. (2002) Dr. Richard Gulliver action plan research into the ecology of Spiranthes romanzoffiana in Scotland. Unpublished report to Scottish Natural Heritage.

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Gulliver, R.L., Gulliver, M. and Sydes, C. (2003) The relationship of a Biodiversity Action Plan (BAP) orchid, Spiranthes romanzoffiana, to grazing in the West of Scotland. Aspects of Applied Biology, 70,143-150.

Gulliver, R. and Gulliver, M. (2004) Looking for Irish Ladies on Scottish Islands:- aspects of the conservation biology of Irish lady’s-tresses orchid Spiranthes romanzoffiana. The Orchid Review, 112(1256), 89-92,106,110,118.

Gulliver, R., Gulliver, M., Keirnen, M. and Sydes, C. (2004) Studies on the conservation biology of Irish lady’s-tresses orchid, Spiranthes romanzoffiana. Glasgow Naturalist, 24(2), 35-68.

Henderson, S.A. (2001) The vegetation associated with Spiranthes romanzoffiana Cham. (Orchidaceae), Irish lady’s tresses, on the Isle of Coll, Inner Hebrides. Watsonia, 23, 493-503.

Horsman, F.C. (1989) The history of recording of Spiranthes romanzoffiana in Britain. BSBI News – the newsletter of the Botanical Society of the British Isles, 53, 18-20. . Horsman, F.C. (1994) Spiranthes romanzoffiana. In: Scarce Plants in Britain. Eds: Stewart, A., Pearman, D. and Preston, C.D. p 398. Peterborough: JNCC.

Legg, C., Cowie, N. and Sydes, C. (1997) The importance of regeneration studies to successful conservation management of Scottish rare plants. Botanical Journal of Scotland, 49, 425-432.

Loder, J. deV. (1935) Colonsay and Oronsay in the Isles of Argyll. Colonsay: Colonsay Press (reprinted 1995, originally published by Oliver and Boyd, Edinburgh).

Lupton, D. (2003) Conservation Biology of Spiranthes romanzoffiana Cham. (Irish lady’s-tresses orchid) – Progress Report. Unpublished report to the National Parks and Wildlife Service, Republic of Ireland.

MacKenzie, A. (2002) Island Voices: Traditions of North Mull. Edinburgh: Birlinn.

MacLeod, N. (2002) Morvern: A Highland Parish (Ed: Thornber, I.) Edinburgh: Birlinn.

Martin, D. and Milnes, K. (1993) An investigation into scarce plants in the locality of the river and Loch Shiel. Unpublished report to Scottish Natural Heritage.

McNeill, M. (1910) Colonsay: One of the Hebrides. Colonsay: House of Lochar (reprinted 2001).

Newton, N. (1990) Colonsay and Oronsay. Newton Abbot: David and Charles.

Pearman, D.A. and Preston, C.D. (2000) A Flora of Tiree, Gunna and Coll. Dorchester, UK.

Robarts, J. (2000) A study of the orchid Spiranthes romanzoffiana on the island of Barra. Hebridean Naturalist, 13, 30-35 + supplementary personal correspondence.

Scottish Natural Heritage (1995) Species dossier: Spiranthes romanzoffiana.

16 Thompson, F. (1974) The Uists and Barra. Newton Abbot: David and Charles.

UK Biodiversity Group (1999) Tranche 2 Action Plans – Volume III: Plants and Fungi. Peterborough: English Nature.

Wilcock, C. (2002) Pollination failure in Scottish populations of Spiranthes romanzoffiana Cham., a rare European orchid. Unpublished report to Scottish Natural Heritage.

8 Acknowledgements

I would like to acknowledge the considerable assistance of the following individuals who provided information or advice pursuant to the current work:-

Dr. Heather McHaffie, Royal Botanic Gardens Edinburgh Dr. Chris Sydes, Scottish Natural Heritage Dr. Neil Cowie, RSPB Scotland Dr. Richard Gulliver, Consultant, Isle of Islay Dr. James Robarts, Amateur Naturalist, Isle of Barra

The following library resources were employed:-

City of Edinburgh Central Library (Scottish Library) National Library of Scotland (inc Map Library), Edinburgh National Archives of Scotland, Edinburgh University of Edinburgh Library Mitchell Library, Glasgow Inverness Central Library and Highland Council Archive Oban Library and Argyll and Bute Council Archive, Lochgilphead

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Appendix

Examples of Spiranthes romanzoffiana habitats on Colonsay and Mull

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