19 Nov 2020

Highlights from the National Seed Bank of Wales

Ardd Fotaneg · Botanic Garden

In 2018 the National Botanic Garden of Wales teamed up with the Royal Botanic Gardens, Kew’s, Millennium Seed Bank Partnership to help launch the National Seed Bank of Wales. Now, as the Millennium Seed Bank is celebrating its 20th anniversary, our fledgling seed bank has turned into a vital resource for conserving some of Wales’ most threatened plants.

The Millennium Seed Bank are the world leaders in seed science and conservation and with their support, Dr Kevin McGinn, Science Officer for Growing the Future, was able to establish our own seed bank. You can read more about his experience of establishing the National Seed Bank of Wales and why seed banks are such a vital resource for conservation in this blog.

I joined the Botanic Garden in 2019 as Biophilic Wales Conservation Assistant – a role which involves collecting and banking seed of threatened and grassland plants in Wales. I was fortunate to have spent a year working at the Millennium Seed Bank on a placement as part of my BSc degree and I am thrilled that I get to use my skills to help conserve Wales’ plants.

 

Why did we create the National Seed Bank of Wales?

The Millennium Seed Bank has collected a vast amount of wild species from around the world and nearly every plant species in the UK. However, as of 2018, 75% of our native flora had not been collected from Welsh populations.

Banking seeds from Welsh populations ensures that genetically diverse seeds best adapted to Welsh habitats are available for conservation and restoration.

Over the last couple of years, we have travelled the length of Wales collecting seeds from critically endangered species from amazing places and habitats.

We are extremely grateful to the Millennium Seed Bank for providing training and continued technical support and for the help of local experts, Botanical Society of Britain and Ireland recorders and Natural Resources Wales.

 

Here are some of the highlights from our collections:

 

Greater Butterfly Orchid – Platanthera chlorantha

We’ve sourced many of our first collections from the Waun Las National Nature Reserve here at the National Botanic Garden of Wales. Waun Las NNR is a working organic farm and a beautiful mosaic of wildflower-rich hay meadows and pastures. The meadows around the reserves have an amazing diversity of flora and one of the star attractions is the greater butterfly orchid.

Although it thrives in Waun Las, it’s now an uncommon sight across Wales as traditional hay meadows have been lost through agricultural intensification. Many grassland wildflowers are less common than they used to be, making them a high priority for seed banking.

Therefore, we have been collecting a wide diversity of grassland species from our reserve, along with the greater butterfly orchid. These collections protect the species, but we can also use the seeds for restoration or reintroduction projects around Wales.

This year we have started a new venture, sustainably harvested seeds from Waun Las National Nature Reserve, to make Welsh wildflowers available for you to create your own meadow at home. Sales help to fund the Botanic Garden’s charitable work, such as the seed bank.

 

Goldilocks Aster – Galatella linosyris

By 2019 the National Seed Bank of Wales was established, and we were ready to venture out across Wales to begin obtaining some of our target species.

That summer we organised a collecting trip to the Great Orme, a stunning outcrop of limestone rock that juts out into the Irish Sea by Llandudno. The combination of thin, low nutrient soil and grazing from the feral goats that roam the outcrop creates beautiful displays of wildflowers from spring through to autumn.

During our trip we collected some of the common calcareous grassland specialists, including common rock rose (Helianthemum nummularium) and carline thistle (Carlina vulgaris). However, we were also targeting a rare inhabitant of the Great Orme – goldilocks aster.

A relative of daisies and dandelion, goldilocks aster likes to grow on the grassy tops of limestone cliffs and slopes. It is a late flowering plant only found in small populations in coastal locations. The Great Orme is home to the biggest population in Wales, but it is also found in small patches along the coasts of Pembrokeshire and Gower where there are similar cliff-top grasslands.

Dr Kevin McGinn and I managed to find a population of goldilocks aster on a steep escarpment where it was growing sheltered from the elements – and the hungry mouths of the Great Orme goats.

A taster of the Great Orme flora, including some of the species we’ve seed banked, can be seen in the ‘Conserving Our Future Zone’ at the National Botanic Garden of Wales.

 

Wild Cotoneaster – Cotoneaster cambricus

The Great Orme is home to endemic plants that can’t be found anywhere else in the country – one such plant is wild cotoneaster.

Cotoneaster cambricus is a gnarled shrub which has never been found naturally at any other location and is the only species of cotoneaster that is native to Great Britain. Not only is it endemic but it is critically endangered at one point there were only six original plants left in the wild.

The population was bolstered by 11 plants grown in cultivation. However, it is still under threat from overgrazing and by invasive non-native cotoneaster species with which it can hybridise. Treborth Botanic Garden were kind enough to donate a collection and we have been collecting fruits from a cultivated plant at the National Botanic Garden of Wales, ensuring the long-term survival of this precarious species.

 

Corn Buttercup – Ranunculus arvensis

Once a familiar sight across our landscape, annual arable plants are now amongst the most rapidly declining plant species in Wales. As farming practices have changed over the last 100 years, plants such as corn marigold and poppies, once so widespread they were considered weeds, are now a rarity.

Several arable species are now virtually extinct in the wild, including shepherd’s-needle (Scandix pecten-veneris) and corn buttercup (Ranunculus arvensis). We were fortunate to have two collections of these rare species donated to the National Seed Bank of Wales by Natural Resources Wales.

Corn buttercup is found in only one field in the Vale of Glamorgan, however, this population is now under threat from development. Steps were taken to save this last population by translocation to a new site and banking seeds from the original plants. These seeds are now stored in the seed bank and we are currently developing a plan to propagate these plants and bulk up the number of seeds.

 

Corky-fruited Water-dropwort – Oenanthe pimpinelloides

Despite the difficulties that the Covid-19 pandemic wrought on the fieldwork season, it has been another successful year for the seed bank. While lockdown restrictions prevented any collections being made in the first half of the year, we switched our focus to species that set seed later in the year.

The first target species was the interestingly named corky-fruited water-dropwort, a rare white-flowered relative of carrots which grows spherical tubers. ‘Corky-fruited’ refers to the spongey tissue that surrounds the delicate seeds.

Corky-fruited water-dropwort is fairly common in parts of England but in Wales its restricted to the Gwent Levels – a unique landscape of floodplain fields, criss-crossed by ditches and waterways. On this trip I was joined by Julian Woodman, Vascular Plants Specialist for Natural Resources Wales, whose knowledge of the flora of Wales is second to none. Members of the carrot family are notoriously difficult identify and as we need to ensure that our collections are correctly identified, having an expert on hand was invaluable.

 

Red Hemp-nettle – Galeopsis angustifolia

In September, Kevin undertook a mission to collect red hemp-nettle seed from one of its three surviving populations in Wales, on Gower. Red hemp-nettle is a small but pretty species that more commonly grows as an arable annual, however, it’s undergone drastic losses in Wales following a similar fate to other arable species.

The populations in Wales now survive on shingle beaches, such as on Gower. However, these populations have a precarious existence. Only 270 plants were found in the Gower population in

2019, but Kevin collected around 200 seeds (10% of the seeds available to limit the impact on regeneration). In England, the Back from the Brink project has been working to restore their populations with the help of collections made by the Millennium Seed Bank. With our Welsh population safely banked, we can do our bit to help conserve the species across the whole of the UK.

 

Purple Gromwell – Lithospermum purpureocaeruleum

Another collection I made this year was of purple gromwell, a rare woodland plant found in a couple of sites along the Glamorganshire coast. Purple gromwell is a creeping woody perennial which was growing up a shaded, slumped cliff.

During the summer, the flowers change from red to purple as they develop, and the chemistry of the cells become more alkaline.

The name ‘Lithospermum’ means ‘stone seeded’ which refers to the fruit of the plant. The fruit has a glossy, white capsule which is incredibly hard and lends the species its name (pictured below).