Skip to main content

Candide Cuttings: Ash Dieback Cost, British Bluebell Advantage and Winter Rapeseed

Published on May 8th 2019
A close up of a flower
Written by Max Thrower

Ash Dieback

The total cost of ash dieback in the UK is expected to reach £15 billion, according to new research.
Ash dieback is a lethal fungal disease that was first found in Britain in 2012, thought to have been imported in on infected ash trees. It is expected to kill over 95% of ash trees.


Fraxinus spp.

Costs arise directly through the clear up of dead trees and indirectly through lost benefits, like air purification and carbon sequestration, that these trees provide.
The cost induced, £15 billion, is 50 times larger than the annual value of trade in live plants to and from Britain. It was calculated by a group of researchers from the University of Oxford, Sylva Foundation, the Woodland Trust and Fera Science.
Dr Louise Hill, researcher of Plant Sciences at the University of Oxford and lead author of the study, said: ‘The numbers of invasive tree pests and diseases are increasing rapidly, and this is mostly driven by human activities, such as trade in live plants and climate change. Nobody has estimated the total cost of a tree disease before, and we were quite shocked at the magnitude of the cost to society.’

British Bluebells

British bluebell
British bluebells aren’t likely to go extinct any time soon, new research suggests.
The British bluebell, Hyacinthoides non-scripta, has shared its UK habitat with a non-native Spanish variety, Hyacinthoides hispanica, and a hybrid between the two, for over three centuries.
There were fears that interbreeding between varieties could mix gene pools to the extent that the British bluebell could become extinct.
However, genetic tests carried out by an international team led by the Royal Botanic Garden Edinburgh (RBGE) found that British bluebells have higher fertility.
Download Candide to your phone to get your daily gardening news
Download on the App StoreGet it on Google Play
The team allowed a mixture of the bluebell varieties to fertilise each other naturally and genetically tested the parentage of the offspring. British bluebells were more successful parents overall.
Professor Peter Hollingsworth, Director of Science at RBGE, said: ‘This research forms part of a long-term study into bluebells in the UK, and there is clearly more to discover before the full impact is known. However, the findings suggest a reproductive advantage to the native bluebells which may limit their risks of being genetically swamped by non-native bluebells.’

Rapeseed Cost

New research suggests that British rapeseed growers are losing up to a quarter of their crop yield per year due to increases in winter temperature.
The research, conducted by the John Innes Centre, linked temperatures between late November and December 21 with the success of yields.
A one-degree increase in temperature in this window costs £16 million in lost yield six months later when the crop is harvested. More significant fluctuations could lead to considerably higher losses of up to £160 million.
Oilseed rape requires a prolonged period of chilling, known as vernalisation, to produce flowers and seed.
The researchers are hoping to produce more productive and stable yields by breeding varieties that are less temperature sensitive.

Related articles

A close up of a flower

Candide Cuttings: Woodland Cover and Climate Change

The Committee of Climate Change (CCC) has issued a report titled 'Net Zero: The UK's contribution to stopping global warming'...
A close up of a flower

Candide Cuttings: Piet Oudolf and New Plants at Chelsea

The Dutch garden designer is most famous for designing the 'High Line' in New York.
A close up of a flower

Slow reads


Candide Cuttings: Orchard Restoration, Naked Gardening and Nursery for Sale

Traditional orchards have declined by 63% since 1950 due to development, agricultural practice change, neglect and changes in...

Love gardens? Sign up for Candide’s Almanac!

A weekly edit of freshly picked gardening tips, travel guides, and the best botanical days out happening near you. Unsubscribe at any time.



About usCareersPrivacy policy

Candide is your guide to visiting UK public gardens. Find the best gardens, buy tickets and enter with just your phone. Download the app for offline tickets, community access and more.

Terms & ConditionsCode of Conduct

© 2022 Candide

Made in Bristol