Crepis foetida Asteraceae 3 sub-species subsp foetida in uk 1 2 3 4




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Crepis foetida – Asteraceae 3 sub-species. subsp. foetida in UK 1 2 3 4

Exhibits dimorphism in involucral bract length and achene beak length. Mention Babcock “The genus Crepis” 1947 5 6

Field characteristics – nodding flower buds, snow-white pappus and bitter almonds (cyanide) smell. 7

Behaves usually as a biennial but can be nearly annual and short-lived perennial 8

Mainland European distribution - W Iran to Maastricht, centred in SE Europe . Declining in C and W Europe

Geographical status of Crepis foetida in UK – New Atlas UK flora and Kent flora

Last known UK sites at Dungeness in 1980 (Walmer 1901, Cumbles 1908, Newhaven 1925, Rye Harbour 1920, Pevensey Bay 1948) 10

Conservation status – schedule 8 species & UK BAP-priority species. Was extinct, now Endangered

In 1991 seeds found at Cambridge University Botanic Garden – Brian Gale

Bid to NCC species recovery programme – first or early plant species. Andrew Deadman, Roger Mitchell, Brian Banks and Jane Sears.

Background search of last sites at Dungeness – all associated with disturbed shingle areas. – last seen at “Oasis” 11

Field experiment to re-introduce Crepis in 1992 at 9 Village sites. 3 shingle textures X 3 interstitial materials – use of transplants and seeds. 12 13 14

Vey early failure because of rabbits - so set up again in 1993, with wire rabbit-proof guards. Parallel plots set up in RSPB reserve but with only half plots caged to verify rabbit factor. 15 16 17 18

Offspring plants routinely very small, single-inflorescence “annuals” and always close (less than 7m) to parent cages. 19 20 21

Both sites monitored for next generation plants maturing to flower until year 2000, after which populations died out by 2002. 22

In 1993 some seeded scrapes set up at same Village sites as in 1992 – all unsuccessful.

In 2000 further sites considered for (re-)introduction– Rye Harbour LNC (last record there in 1920).chosen. Barry Yates. 23 24

In 2000 transplants placed under wire cages along shingle ridge used for war-time railway track (compacted shingle with cinders). Site already used for Lactuca saligna and Little Terns., so fox-proofed

These flowered but produced very few offspring, generally in parent cages.

Rabbit-proof fencing in place at Rye in2005. Led to immediate increase in numbers of plants.

Rye populations continue to survive to present day, but require shifting landscape. 25

In 2001 decided to investigate chalk quarries as potential sites for introductions.. Based on past records and site at Maastricht, Holland.(Dr Douwe Th. De Graaf at Natural History Museum) 26 27 28

In 2003 transplants (30-50) placed in 3 chalk quarries: 1. Peters Pit, 2. Crundale Pit, 3. Nonnington pit. 29 30 31 32

Subsequent populations grew and then died out over a few years – slightly more persistent at two worked quarries. 33

Chance event in 2003 – 2 pot-grown plants, transplanted into Northiam garden, flowered and set seed. 34

Constant monitoring was possible which provided lots of useful data: 35

1 no rabbit problem,

2 most germination in late Summer and Autumn and best in dry periods,

3 better seedling survival in cold Winters (reduced losses to molluscs)

4 moist and warm Spring and early Summer promoted flowering..

Population has persisted and increased and spread slowly- large population fluctuations. 36

Summary of established populations at time of BW paper (2010)– still continuing at Rye Harbour and Norhtiam. Lost from village, RSPB sites and chalk sites. 37

Mobile phone call in 2010 from Dorothy Beck- Crepis in my garden at Lydd-on-sea 38

Subsequent surveys showed large population growing in lawns, kept short and thin by occasional scarification. 39 40

Assumed that this population had been overlooked or non-existent in 1991

Population continues to survive but with big variations from year to year. 41

Two published side products: EN “Dungeness before 1960: the landscape and the people” concluded Dungeness had changed a lot: Paper by Squirrel et al (2006) “Assessment of genetic diversity in populations of Crepis foetida” Watsonia 26: 121-126 – concluded no inbreeding problem.

UK distribution in 2002 (Preston et al New Atlas of the British Flora) 42

Current state of play – three populations more-or-less established, at Rye Harbour intentionally, at Northiam unintentionally and Lydd-on-sea probably already there. 43
Reading
Ferry, B. et al (2010) Stinking Hawk’s-beard – a reluctant candidate for Species recovery. British Wildlife 21 (4): 255-260.

Ferry, B. & Beck D. (2004) Dungeness before 1960: the landscape and the people. English Nature Research report 571.



Squirrel , J. et al (2006) Assessment of genetic diversity in populations of Crepis foetida L. (Asteraceae). Watsonia26: 121-126


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