Monday, 1 February 2016

Corn Cleavers: Endangered and unloved

BSBI received an interesting invitation last week from ARKive, the multimedia guide to international endangered species. They wondered if BSBI would like to nominate an unloved and overlooked plant for a global Valentine's Day poll to find the species most deserving of our love. 


Corn Cleavers - note the diagnostic fruits
Image: Ian Denholm
Ian Denholm proposed Galium tricornutum Corn Cleavers and here is why we think this plant deserves your love:

 ·         Name of species:
 Galium tricornutum Corn Cleavers (Rubiaceae)

·         Conservation status:
 Critically Endangered: GB Red List 2005; England Red List 2014.

·         Why the Botanical Society of Britain & Ireland love it:

This may be Corn Cleavers’ last chance to find love. Unlike Coffee and Gardenia (in the same family) nobody longs for Corn Cleavers in the morning or swoons at his scent. Formerly a widespread “weed” among cereal crops but - unlike Centaurea cyanus  Cornflower and Agrostemma githago Corncockle – nobody wants the unshowy flowers of Corn Cleavers in their 21st Century Wildflower Seed Mix. Easily confused with Galium aparine Common Cleavers or Sticky Willie, but Corn Cleavers is much less common and not so clingy.

·         Threats to Corn Cleavers survival:

Corn Cleavers has declined drastically due to increasing agricultural intensification and only one viable population now remains in Britain – it needs the regular cycle of disturbance enjoyed back in those traditionally-managed cornfields. Although it comes up occasionally as a casual, eg in Newcastle in the C19th and in Cambridgeshire in 1996 following disturbance due to road works, Corn Cleavers cannot persist in such surroundings. 

Ian Denholm examining arable weeds
 at Rothamsted Research
Image courtesy of I. Denholm
·Information on BSBI's work with this species:

BSBI’s volunteer members continue to record and map any sightings of Corn Cleavers across Britain and Ireland and our expert plant referees confirm any identifications. We monitor the one remaining viable population in Hertfordshire and our Head of Science has been working with the Oxfordshire Rare Plants Group to reintroduce it to a site where it once occurred. Seed from Hertfordshire has also been sown in an arable weed reserve in Buckinghamshire and is stored in Kew’s Millenium Seed Bank.

You can also see this profile of Corn Cleavers on the ARKive website here. Note that this is an international poll so Corn Cleavers may not get many votes in Australia, where we are told it is a pest! 

Please show your love for Corn Cleavers, and your support for the work BSBI is doing to conserve it in England, by voting in the ARKive poll here.