Current status
Juniper is divided into at least two subspecies with frequent intermediates. Subspecies communis ranges from a spreading shrub to erect tree, while subspecies nana is a procumbent, matted shrub. There is possibly a third subspecies (hemisphaerica) from maritime cliffs in Cornwall and Pembrokeshire, but this requires confirmation. Overall, juniper has an extensive, but rather discontinuous distribution; it can tolerate a range of climatic and edaphic conditions, and it forms a component of a number of British plant communities. Subspecies communis can be regarded as a successional shrub, opportunistic in its pattern of establishment and quickly shaded out as scrub thickens or an over-topping woodland canopy develops. This subspecies has two main population centres, in the Scottish Highlands and the chalk downs of southern England, but it has important populations elsewhere. Subspecies communis forms unusual thickets on sand dunes on the north-east coast of Scotland. Subspecies nana is largely restricted to north-west Scotland as a component of montane heath vegetation.
Data at the Biological Record Centre (BRC) suggests that there has been a 60% decline in the number of occupied 10 km squares up to 1960, but the data are known to be incomplete. The most detailed recent study, in Northumbria, only covered the period from 1973 to 1995. Nevertheless there was an overall population decline here of 30%, while 54% of colonies showed a decline in numbers and 16% of colonies became extinct. The long life of the adult bushes means that moribund populations with no regeneration may be recorded for a very long time, although they can be regarded as functionally extinct. No quantitative data are available on the decline of subspecies nana, but the total extent of larger stands of Calluna vulgaris - Juniperus communis ssp nana heath (NVC class H15) is estimated at just 805 ha. It is known that burning can reduce this vegetation to a fragmentary cover from which recovery may be very slow.
Juniper receives general protection under the Wildlife and Countryside Act 1981.
Current factors causing loss or decline
Excessive grazing which prevents establishment of young bushes.
Insufficient grazing which reduces the area suitable for juniper regeneration. This may also cause the loss of adult bushes as tree recuitment leads to increased shade.
Direct clearance of stands.
Excessive burning which may destroy young regeneration and adult bushes.
Low economic and cultural value attached to the species.
Current action
ITE is surveying the current status and distribution of the species in England, continuing demographic monitoring and pathological investigations at Porton Down and researching ways to manage and reinstate subspecies nana and its associated vegetation community on Harris.
An English Nature study in Northumbria has lead to a Wildlife Enhancement Scheme Initiative which aims to maintain and extend the area and improve the quality of juniper habitats in the area.
FC is studying regeneration and methods of establishment at Glenlivet in Speyside and Glen Garry in Lochaber.
Many juniper populations are included in designated sites. For instance in the Scottish Borders 37 out of 71 juniper sites are in SSSIs, whilst 31% of bushes recorded in an extensive survey of populations in southern England were in protected areas. Some SSSIs have been notified primarily to protect juniper. Subspecies nana is found in the Cairngorms NNR, and on at least five SSSIs in north-west Scotland.
Juniper occurs in a number of habitat types listed under the EC Habitats Directive, and juniper scrub has been recognised as a nationally scarce woodland type.
An action group involving SNH, the Forestry Commission, Highland Birchwoods, the Scottish Agricultural College, National Trust for Scotland and Plantlife has been set up to increase interest in, and develop management prescriptions for, montane scrub woodland of which juniper would be a natural component in many areas.
Action plan objectives and targets
Maintain the current range of juniper
Maintain the overall population size of juniper.
Achieve natural regeneration of juniper populations at sites under direct conservation management
Maintain, or re-establish, populations at sites not under direct conservation management.
Restore representative tree-line juniper populations.
Proposed actions with lead agencies
Policy and legislation
Use the FC Woodland Grant Scheme as a means to maintain populations within the woodland context. This includes measures to encourage the restoration of sub-alpine scrub with juniper where appropriate as the upper limit to native woodland schemes. (ACTION: FC, SNH)
When next reviewed, consider how the Scottish Countryside Premium Scheme, the Countryside Stewardship Scheme, Tir Gofal and other agri-environment measures could benefit the species. (ACTION: MAFF, SOAEFD, WOAD)
Take into account the ecological requirements of juniper when seeking to influence the reform of CAP with respect to the management of semi-natural rough grazing land. (ACTION: MAFF, SOAEFD, WOAD)
Site safeguard and management
Consider the best examples of juniper habitat which meet local or national criteria for notification as SSSIs. (ACTION: CCW, NE, SNH)
Assess site management in reserves and designated sites where juniper exists and ensure that site management permits the natural regeneration of juniper in part at least. (ACTION: CCW, NE, FC, SNH)
Maintain existing populations outside SSSIs wherever possible by encouraging landowners to manage their land in ways that encourage juniper, and by offering advice and practical assistance for such management. (ACTION: CCW, NE, FC, MAFF, SNH, SOAEFD, WOAD)
Species management and protection
Assess the desirability of reintroducing juniper at former sites in regions of the UK in which the species has declined significantly. Undertake trial reintroductions where appropriate. (ACTION: CCW, NE, SNH)
Advisory
Advise relevant landowners and managers of the presence and importance of juniper, and of the appropriate management for its conservation. (ACTION: CCW, NE, FC, SNH)
As far as possible, ensure that relevant agri-environment project officers are advised of locations of this species, its importance and of the management needed for its conservation. (ACTION: CCW, NE, FC, MAFF, SNH, SOAEFD, WOAD)
Develop and issue best practice guidance to encourage the maintenance and regeneration of juniper in woodland communities. (ACTION: CCW, NE, FC, SNH)
Develop and issue best practice guidance to encourage the restoration of treeline scrub woodland with juniper as a component. (ACTION: CCW, NE, FC, SNH)
Future Research and Monitoring
Review the taxonomic status of subspecies hemisphaerica and intermediates. (ACTION: CCW, NE, SNH)
Update the BRC database on the species to act as a base line for regional assessments of local conservation requirements for the species. (ACTION: CCW, NE, SNH)
Develop and carry out a programme for regional survey to assess the extent, age range and reproductive potential of juniper populations, classifying populations according to the risk of loss and potential for survival. Use the results of this survey to set priorities for regional action to maintain and, where necessary, restore populations. (ACTION: CCW, NE, SNH)
Identify suitable areas where new populations of juniper can be established to contribute to habitat biodiversity and replace unavoidable losses of existing populations. (ACTION: CCW, NE, SNH)
Undertake research into optimum levels of grazing disturbance and habitat management to encourage germination, regeneration and development of juniper. (ACTION: CCW, NE, FC, SNH)
Review methods for establishing juniper. (ACTION: CCW, NE, FC, SNH)
Clarify the classification of juniper communities within the British NVC. (ACTION: SNH)
Encourage research into possible sustainable economic uses of juniper as a means to encourage an expansion in the area of semi-natural juniper vegetation and to enhance management of existing areas. (ACTION: CCW, NE, FC, SNH)
Communications and Publicity
Ensure that the significance of juniper, the threats to it and suitable management to maintain it are publicised, particularly in relation to the different land management systems in which it occurs - forestry, agriculture and recreation (the latter including deer stalking and shooting estates). (ACTION: CCW, NE, FC, MAFF, SNH, SOAEFD, WOAD)
Support a publication on the significance to biodiversity of montane scrub woodland including juniper as a component. (ACTION: CCW, NE, FC, SNH)
Continue and expand the exchange of information on the ecology and habitat requirements of juniper with European counterparts. (ACTION: CCW, NE, SNH)
Links with other action plans
None given.