Heather landscapes under threat due to climate change

Press release
Published : 04 Sep 2019

One of England’s celebrated landscape spectacles is suffering due to climate change as the impact of last year’s hot weather and increased pest activity has turned acres of heather from glorious purple to a muddy brown.

Through August and into early September, the hills at Long Mynd in Shropshire and at Holnicote on Exmoor are typically awash with a haze of purple.

But this year the National Trust, which cares for both landscapes, has seen up to 75 per cent of the heather in poor health due to a combination of last year’s drought and damage from the heather beetle.

Peter Carty, Countryside Parkland and Gardens Manager for the conservation charity in Shropshire said: “Last year’s high temperatures, and subsequent lack of rain, damaged a large area of heather and it is clear from the orangey brown colouration this year that the plants are seriously stressed and unlikely to flower.

“The milder winter also led to an increase in the heather beetle numbers, which are a natural element of the heather ecosystem, as it wasn’t cold enough to kill off their larvae.  The beetle affects heather by damaging the outer layers of the leaf, making it more susceptible to drought stress.

“In places where heather was sheltered from the extreme or where damp conditions were present, the heather has survived. However, there will be no mass flowering this year.” 

The lack of blooming heather has serious impacts on other wildlife, such as the red grouse and Emperor moth, which in its caterpillar stage, rely on the plant for food. 

Keith Jones, climate change specialist at the Trust added: “We are seeing first-hand the impacts of climate change on at least two of these special landscapes within our care.  Last year’s prolonged hot summer vastly restricted the supply of water to the plants.  This together with the lack of rain over the winter and first half of the year has not been enough to replenish the plants.

“With warming temperatures other trees and plants are increasingly more susceptible to pest and diseases.  We have seen changes in the tick population with increases of over 400 per cent in the last 10 years and plane tree wilt, particularly in London, is magnified when there are drought conditions.  We are also more susceptible to an increasing number of moorland fires – like the one at Easter earlier this year on Marsden Moor.

“Pest and diseases are inexorably linked to how we live (global trade and poor biosecurity on the plants we import which allow new pest and diseases to get a foothold) but climate change is a big multiplying factor creating the stress which allows diseases to get a foothold and multiply.” 

The team at Holnicote on the edge of Exmoor in Somerset, another uplands area, are already working on a solution to help with the land drying out by planting more trees to help slow the flow of water further up the valley as part of its Riverlands[1] project. It is also restoring wet habitats such as blanket bogs and mire which hold water in high rainfall and release is slowly in times of drought. 

It is also thought that an unexpected side effect of the prolonged warmer weather could be the proliferation of the heather shield bug – a natural predator of the heather beetle.

Basil Stow, Area Ranger for the National Trust added: “We are seeing damage across hundreds of acres of heather and on our neighbouring land.  One of the unfortunate consequences of the heather suffering is that tougher plants such as Molinia have chance to take hold.  Heather is a resilient plant and capable of regenerating from the rootstock or from seed – so we will need to watch and wait to see what happens next year but we are hopeful that it will recover with careful management.”