Cornflower is an annual plant of arable fields, often on sandy, acidic soils. Flowers are self-incompatible and are borne between May and August. The seeds, which are believed to remain viable for several years, generally germinate during the following spring with a second flush in late summer. This species was often found in association with corn marigold (Chrysanthemum segetum), which also germinates in spring.
Cornflower once occurred throughout the UK and was a troublesome weed of arable land. Between 1930 and 1960 it was recorded from 264 ten km squares, but by 1985 it had declined to fewer than 50 ten km squares. Today, self-sustaining populations are thought to be confined to only one site in Suffolk, one on the Isle of Wight and one in Lincolnshire. Isolated plants still occur over a large area of the south and east of England and in Wales, although many are due to introductions from wildflower seed mixtures and most persist for no longer than a year. Large numbers sometimes occur when there are deep excavations for roads and pipelines. In Europe as a whole, cornflower is not threatened and is still widely distributed, although it has declined in much of north-west Europe.
In GB cornflower is now classified as Endangered. It receives general protection under the Wildlife and Countryside Act 1981.
Current factors causing loss or decline
The following agricultural changes were largely responsible for the decline of cornflower and are now providing constraints on its recovery:
Increased use of herbicides and fertilisers.
The development of highly competitive crop varieties.
The destruction of field-edge refuges.
The demise of traditional crop rotations.
The conversion of marginal arable land to pasture.
Research is ongoing at the Suffolk site to determine the ideal conservation management.
The Suffolk and Isle of Wight sites are under Countryside Stewardship Scheme agreements.
Cornflower has been introduced to several trial arable weed conservation plots such as that at Barton Downs (English Nature).
Action plan objectives and targets
Develop and maintain viable populations at all extant native sites where the species is long-established.
Achieve the natural colonisation of new sites.
Establish populations of cornflower 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 cornflower 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 cornflower included in wildflower seed mixtures is of native origin. (ACTION: MAFF, WOAD)
Site safeguard and management
Continue beneficial management at the Suffolk site, implement management at the other three 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 cornflower sites, thereby providing opportunities for its spread. Favourable management will include the relevant options under appropriate agri-environment schemes, eg 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 cornflower from the seed bank, seeking opportunities through appropriate agri-environment schemes. (ACTION: NE, MAFF)
Collect seed from all extant native sites and any restored sites and deposit in the Millenium Seed Bank at Wakehurst Place (Kew). (ACTION: CCW, NE, RBG Kew)
On sites where cornflower is 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: NE, MAFF)
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 cornflower. 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 on the Suffolk site, and extend to other 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 the 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 cornflower and other threatened arable species. (ACTION: NE, 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
Originally published in: UK Biodiversity Group Tranche 2 Action Plans - Volume I: Vertebrates and vascular plants (June 1998, Tranche 2, Vol I, p149)
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