Summary: Conservation means conserving within-species genetic variation as well as the species themselves; there is currently no national strategy for English native plants to do that. In the blog I point to examples of regional genetic variation/ecotypes and suggest local seed would be the most cost-effective biodiversity-rich climate-change-resilient option to use for the basis of creating new grasslands within the government’s 25 Year Environment Plan, and it would also conserve England’s native plants.
If we are to conserve earth’s biodiversity we must try to conserve both the species and as much of the genetic variation within each species as we can. Gene diversity is something that gets attention in conservation when dealing with a very small population of animals* or birds where the concern is the health problems associated with inbreeding, but rarely considered when we think of common plants whose ecotypes may be found across many different habitats or exhibit geographic variation. Given the likelihood of additional challenges to conservation from climate change, we have need of the broadest range of genetic variation possible as a starting point from which to expand the UK’s semi-natural habitats to maximise our chances of success in creating new robust ecosystems.
I asked if Natural England had a strategy for conservation of genetic diversity within plant species and they do not (RFI 5205), with the exception of crop wild relatives which is a specific biodiversity indicator in “Biodiversity 2020: A strategy for England’s wildlife and ecosystem services” and is currently under review. To be fair, I had already guessed Natural England didn’t have one following a previous question asking if there was any plan to replicate the gene-bank within each SSSI designated for its grassland (TO2018/27538), such that if one was irreparably damaged we had a genetic copy. I asked because I noticed one of the three grassland SSSIs in my area had been damaged and I was concerned our only inland population of dyer’s greenweed** had been destroyed (the SSSI had been damaged but the population was still there – the local team checked & reported back to me). There is no plan to make genetic copies of grassland SSSIs or indeed any plan for creating such a plan that I am aware of, which is odd to say the least because Natural England strategies all point to SSSIs being the cornerstone from which our native biodiversity will spread in the future. With plants, most seed will only spread from SSSIs if you physically pick up the seeds and move them to a new site (this chalk grassland paper suggests >100 years for seeds to move and grow naturally elsewhere https://onlinelibrary.wiley.com/doi/abs/10.1111/avsc.12076 but it’s a bit more complicated than that, as you can imagine); if no-one is planning to move those seeds then the 25 Year Environment Plan as a vehicle for native plant conservation has failed before it even starts because it doesn’t address that within-species genetic variation. And that’s just the SSSIs; the local species-rich ancient grassland sites (Local Wildlife Sites, Sites of Nature Conservation Interest) are all under the umbrella of planning rather than conservation and have been steadily damaged (see this from the Wildlife Trusts, shocking in 2014 and it’s probably worse now https://www.wildlifetrusts.org/news/save-our-vanishing-grasslands-petition-goes-top ) and as I have found in my area there is no way of stopping damage from happening or punishment to the landowner afterwards. The local sites aren’t even on the radar for seed use, let alone part of a national strategy.
You might wonder if there is evidence to show regional genetic variation within plant species – well there is – colour variation in the keel of common bird’s-foot-trefoil flowers is a satisfyingly fascinating story https://botsocscot.wordpress.com/2020/06/22/plant-variation-and-citizen-science/ , this paper about the effect of genetic diversity on vegetation influence of yellow rattle https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/1365-2745.13050 , and then this splendid and disturbing review of the subject from 2004 that seems to have got lost down the back of Natural England’s sofa “A review of the potential effects of seed sowing for habitat re-creation on the conservation of intraspecific biodiversity. Defra Contract BD1447.” – search and it pops up as a Word .doc to download. This study from Germany on genetic variation within grassland plants and the need for seed collection zones https://besjournals.onlinelibrary.wiley.com/doi/10.1111/1365-2664.12636 And for those old enough to remember – a thank you to the Flora Locale website which influenced me greatly many years ago; their documents are now held here https://cieem.net/i-am/resources-hub/ .
At the scale of ecotypes, in the past botanists were familiar with the early-flowering common knapweed of floodplain meadows as noted in Marrsden-Jones and Turrill’s 1954 book on British Knapweeds, though I doubt many people reading this will have consciously seen and noted it. There is a similar version of devil’s-bit scabious and I have observed the same in great burnet – the floodplain ecotype flowering and seeding earlier than those plants remaining in the tiny relics of the once vast medieval grazing moors. There is the devil’s-bit scabious ecotype that grows in acidic dry soils and another on marshy clay ones. Sell and Murrell in their introduction to the first published volume of their British Flora https://bsbi.org/variation-in-sell-murrells-flora point out bulbous buttercup has variants that grow on chalks, the sands and the clays. Micro-species are better known now, but those within the Goldilocks buttercup group haven’t yet been fully described and some microspecies grow in grassland not woodland and could well be endemic – mentioned second in this blog by Brian Eversham https://www.wildlifebcn.org/blog/wildlife-trust-bcn/here-and-nowhere-else . Grasses too can show ecotypal variation – just look at how Stace 4 separates up the red fescue aggregate. And it wouldn’t be a piece of writing on variation without the many microspecies of dandelions being mentioned, would it?
However, there is no robust scientific evidence that a seed mix from a limited genetic collection bulked up commercially (i.e seed produced by a seed firm) will create an equivalent grassland community (e.g. MG5) which is as good as or better than using local seed from sites which show a “long continuity of ‘traditional’ management” (ancient grassland) and yet using commercial seed mixes is what is happens generally for creating new grassland habitat. I’m using HS2 as a case study to check what current official conservation practice is – HS2 don’t record the seed source for new grassland communities and only specify that it create a similar plant community (FOI-19-3407 – contractor takes decisions within guidelines given; I haven’t been in contact with the contractors yet) and government departments do similar except in large projects like https://www.devonwildlifetrust.org/what-we-do/our-projects/culm-grassland-natural-flood-management-project for the Environment Agency and for Natural England the High Weald Landscape Trusts Weald Meadows Partnership (WMP) where local seed is used. It may be that no-one has done any such scientific comparison, but I cannot see how a seed mix of limited genetic variation can ever be a better way to start a new grassland community than green hay from a local ancient grassland and a seed mix is definitely not conservation for England’s grassland plants.
I’ve not been able to find any data on comparative costings between using a seed mix and local seed, and I rather doubt anyone has yet put a cost on ‘loss of genetic diversity to future generations’. If we are in an era where we cost our local biodiversity in monetary terms then this lack is rather glaring. I would suggest that using local seed is the cheaper option as it conserves local habitats (they become needed for their seeds and so would be looked after better) and frequently the cut hay from such sites is surplus to requirements and therefore costs little more than transport and someone to spread it around the recipient site.
Given the willingness of the environmental agencies to ‘work together’ (a euphemism for there being no public money to achieve their objectives; how often have you seen road building requiring cooperative action of local volunteers or charities to lay tar-mac? Well quite.) then using local seed for habitat creation could easily be written into any guidelines and should be, but I suspect it will take legal action to force this government to change. It might even be that the chair of Natural England thinks legal action is required too, for I notice he has sensibly been publicly vocal about how funding cuts have prevented Natural England from carrying out their 500 or so statutory duties or responsibilities properly https://committees.parliament.uk/committee/62/environmental-audit-committee/news/127536/natural-england-finances-squeezed-by-government-making-biodiversity-protection-challenging/ Do his comments now put the legal responsibility of conserving England’s biodiversity back onto Defra or the Treasury and away from Natural England? I hope so because we really do need the experts within Natural England and the diversity of training that only they can give our future experts.
UPDATE 18 February 2021
Thanks to Miles King who let me know that Margaret Palmer wrote “A Strategic Approach to the Conservation of Plants in the United Kingdom” in 1997 https://www.jstor.org/stable/2404765?seq=1 for the statutory nature conservation agencies and he wrote about a “plant conservation strategy : a future for Britain’s wild plants” via Plantlife the year before in 1996 https://www.aspergillus.org.uk/books_and_theses/plantlife-link-plant-conservation-strategy-a-future-for-britains-wild-plants/ which is not currently available digitally.
*I wondered if it was just plant conservation but it may be to do with larger populations as I asked Defra (EIR2020/22996) if there was any written record that they had assessed whether the eradication program they are undertaking of the legally-protected mammal the badger would destroy any of the genetic variation present within the UK population. There was no written record, so I have to assume no genetic assessment was carried out prior to killing all the badgers in the specified areas of the country; perhaps that was the idea – you can’t find what you don’t look for?
**since then two new but small populations of dyer’s greenweed have been found in the area, one on private land and one on land of unknown ownership.
The answer for TO2018/27538 was given to me at the end of January 2019 and Natural England also gave me a contact to discuss the issues I’d raised. I haven’t been in contact yet because I’m making sure I’ve got enough evidence for the things I think should be changed in England’s conservation policy first. This blog is also me thinking out loud about what I want to write in my book and seeing what the weaknesses are to my arguments. If you are in Natural England and reading this, I’ll be in touch eventually: I’m slow, sorry.