Current status
Red hemp-nettle is a species of arable land, found mostly on calcareous soils but also on coastal sands and shingle in the southern counties of England and Wales. Its distribution is correlated with open vegetation on well drained soils in sunny locations with low rainfall. It is a summer annual which tends to germinate in spring. Consequently, many plants are eradicated during harvest or by early autumn cultivation before they have set seed. It is therefore most frequently encountered in spring-sown crops.
Red hemp-nettle has shown a severe decline since 1930. It has been recorded from a total of 116 ten km squares since 1970, but has been seen in only 61 of these since 1980. Elsewhere, it is found in western, central and southern Europe, eastwards to Poland and Bulgaria. It is rare in north-western Europe.
In GB this species is classified as Nationally Scarce. It receives general protection under the Wildlife and Countryside Act 1981.
Current factors causing loss or decline
Widespread use of herbicides and fertilisers.
The development of highly productive crop varieties.
Destruction of field-edge refuges.
Autumn cultivation which destroys plants before they have set seed.
The demise of traditional crop rotations and cultivation on marginal arable land.
Recreation and tourism on coastal sites may be important factors, but further research is needed to clarify their significance.
Current action
Coastal populations at Snettisham and Dungeness (England) and Gower (Wales) are protected within SSSIs.
Action plan objectives and targets
Maintain the geographical range of this species in the UK.
Increase the total population size of this species in the UK.
Achieve the natural colonisation of new sites.
Establish populations at eight sites within the historic range by 2003
Establish an ex-situ programme to protect genetic diversity, create a reserve population and provide experimental material.
Proposed actions with lead agencies
Policy and legislation
Encourage the development of relevant agri-environment schemes, such as the pilot Arable Stewardship Scheme in England, as a potential means of re-establishing red hemp-nettle in the countryside. When reviewing such schemes, consider whether changes are needed to increase their potential benefits for this and other threatened arable species. (ACTION: CCW, NE, MAFF, WOAD)
As far as possible, ensure that any seed of red hemp nettle included in wildflower seed mixes is of native origin. (ACTION: MAFF, WOAD)
Site safeguard and management
Continue with beneficial management at key sites, implement management at other extant sites and refine techniques as the results of research continue to emerge (ACTION: NE)
Seek to develop a network of suitable habitats within the vicinity of these species sites, thereby providing opportunities for its spread. Favourable management will include the relevant options under the appropriate agri-environment schemes e.g. uncropped headlands (ACTION: CCW, NE, MAFF, WOAD)
Species management and protection
Undertake experimental management at eight carefully selected historic sites with the aim of regenerating these species from the seed bank, seeking opportunities through appropriate agri-environment schemes (ACTION: NE, MAFF)
Assess the feasibility and desirability of reintroducing these species at selected sites should regeneration from the seed bank prove unsuccessful (ACTION: NE, JNCC)
Collect seed from a representative number of sites in different parts of the range of this species and deposit in the Millenium Seed Bank at Wakehurst Place (Kew). Plants should also be propagated for reintroductions if necessary. (ACTION: CCW, NE, RBG Kew)
Advisory
On sites where these species are a significant consideration, advise landowners and managers of the presence and importance of this species, specific management for its conservation and any potentially damaging actions. Particular attention should be given to optimal cultivation and harvest times. (ACTION: NE)
As far as possible, ensure that all relevant agri environment project officers are advised of locations of this species, its importance, management requirements and potential threats. (ACTION: CCW, NE, MAFF, WOAD)
Future Research and Monitoring
Collate information and resurvey extant and historic sites where necessary in order to gain a more complete understanding of the current distribution and status of these species. This will determine the range over which conservation action is appropriate and help to clarify the threats to remaining populations.(ACTION: CCW, NE, JNCC, SNH)
Continue with monitoring and research work extend to sites with extant and restored populations with a view to refining conservation management techniques. Where possible monitoring visits should be combined with meeting landowners to discuss conservation management for these species. (ACTION: NE, JNCC)
Undertake research to determine the selectivity of all graminicides currently in use so as to identify which, if any, are suitable for use in field margins that support this and other threatened arable species. (ACTION: JNCC)
Communications and Publicity
Publicise the plight of this and other threatened arable species. Articles should be written for relevant conservation and farming magazines and newsletters. Botanists should be encouraged to report any new records, eg through Atlas 2000 recording. (ACTION: CCW, NE)
Develop links with European ecologists working to conserve threatened plants of arable habitats. (ACTION: JNCC)
Establish arable conservation display and education centres with the aim of raising public awareness of this threatened group of the UK flora. (ACTION: CCW, NE)
Links with other action plans
None given.
Publication details
Originally published in: UK Biodiversity Group Tranche 2 Action Plans - Volume I: Vertebrates and vascular plants (June 1998, Tranche 2, Vol I, p177)
Related links
ARKive Visit the ARKive website to view images and further information relating to this species