Buckinghamshire project to boost bush numbers across five sites
A special blend of ‘super seed smoothie’ is being used to try to halt the decline of junipers in the Chilterns – with the goal of encouraging their long-term re-establishment across five sites.
The specially formulated (just for plants!) juice aims to ‘bolster the juniper’s natural regeneration through seed collection, germination and propagation.’
Experts say juniper bushes are in decline. This is despite being characteristic of chalky grasslands and lowlands in the southern part of England. It’s classed as important for the country’s biodiversity and the scheme aims to protect the plant from habitat loss.
The National Trust scheme is being funded by the Natural England Species Recovery Programme with conservation work being undertaken in partnership with Kew Garden’s Millennium Seed Bank.
To create the smoothie, juniper berries are whizzed up with sand, warm water and eco detergent, which helps to strips the oils away from the seeds using a recipe from the Buckinghamshire and Milton Keynes Environmental Records Centre.
Made up of over 150,000 seeds collected from the berries of the declining species at West Wycombe, Bradenham, Coombe Hill, Pulpit Hill and Watlington Hill, the smoothie mix is spread over exposed bare chalk.
It’s hoped that doing so will help to move fertile seeds to suitable ground to provide the plants with the best conditions for growth.
Teams aim to deter browsing deer from eating any emerging young juniper seedlings, hawthorn branches are laid over the newly spread seeds.
Providing plants with best conditions for growth
‘By collecting the berries and turning them into a smoothie, we are able to remove oils which inhibit germination,’ explains Matt Livarski-Bond, ranger for the National Trust in the Chiltern Hills.
‘This is the same process as what would happen if they passed through the digestive system of any land animals and birds which eat them.’
‘It’s a very messy process – the berries are super sticky – and quite pungent. The ranger’s workshop will be smelling of gin for quite some time.’
The smoothie is then put in a sieve and rinsed in a bucket of warm water to wash the seeds clean, before spreading them out to dry off to stop the mix going mouldy. Once dry the seeds are finally mixed with dry sand to aid distribution.
The sprawling evergreen shrub, more often associated with gin, attracts a wide variety of insects, mammals and birds including song thrush and fieldfare that feed off the spiky plant’s berries.
The coniferous species has also struggled with competition from yew trees and a lack of ground disturbance preventing seeds taking root due to a lack of suitable niches.
National Trust rangers have created a series of scrapes across the Chiltern landscape, removing the topsoil to provide a more suitable seeding ground and improve the effectiveness of the seed-smoothie.
Collecting juniper berries at Pulpit Hill, Buckinghamshire. Image: Katy Dunn / National Trust Images
Improving quality of berry collection
‘Junipers are not particularly fertile plants, as their reproduction depends in large parts on the proximity of male to female bushes, as well as other environmental factors such as pollution,’ explains Matt.
‘At one of the project sites, Pulpit Hill, we found that berries were practically all infertile, with the nearest male plant located in Bradenham, which is seven miles away.’
‘This forced the Pulpit Hill junipers to rely on one singular plant to disperse its pollen. Overall, only 2 per cent of berries we harvested had viable seed, so these plants stood very little chance to reproduce on their own.’
Further efforts to safeguard the species are taking place at the Kew Millennium Seed Bank where juniper berries collected last year have been cleaned to remove the majority of dead and empty seeds.
They were also germination-tested to inform future conservation efforts by improving the quality of the berry collection.
The seeds are now with a specialist plant propagation company who will germinate the seeds and grow thousands of new juniper plants which will eventually be brought back to the Chilterns and planted on the sites that the seed originated from.
‘Juniper is such an iconic species in the British landscape, but in general it is not as well recognised as other UK woody plants,’ says Dr Chris Cockel, UK Conservation Projects Coordinator at the Kew Millennium Seed Bank.
‘This project is not only helping to revitalise the aging population of Juniper in the Chilterns but is also raising awareness of the threats facing this species and the urgent action that needs to be taken to halt its decline.’
Raising environmental awareness
‘Working in partnership with the National Trust is so important for us at Kew, combining our resources and know-how to safeguard this and other plant species and to halt the biodiversity crisis that the natural world is facing.’
The project hopes to increase the number of junipers in the Chilterns by decreasing the distance between female specimens and their male counterparts, thereby allowing them to reproduce more effectively in the future.
‘It is very exciting to see this collaborative and innovative conservation method in action, made possible by funding from Natural England’s Species Recovery Programme Capital Grant Scheme,’ says Jess Aldred from Natural England.
‘With so many of our native species threatened with extinction, we do sometimes have to think outside the box when it comes to conserving them to ensure that they are not lost from Britain.’
‘We are delighted to be supporting this project which is helping address the Environment Act target to reduce the risk of species extinction, and we very much look forward to seeing results.’
