Infrastructure

The great tree clearance: does Network Rail need to grow up?

Network Rail’s ruthless new tree clearance plans have drawn the ire of the public and environmentalists alike. ALThough trackside trees cause well-documented problems for the railways, has the organisation taken things too far? Joe Baker investigates

For UK rail infrastructure owner Network Rail, managing vegetation alongside train tracks is vital to ensuring smooth and safe railway operations. Nevertheless, some environmental groups argue that the organisation's overly reckless tree felling activity has had a severe impact, not only on the UK’s tree population, but on the wildlife that call them home.


In May, the UK's Guardian newspaper revealed evidence that Network Rail was planning a five-year vegetation management programme across 20,000 miles of its tracks. An internal document reportedly highlighted a threat to millions of trees across the network, with Network Rail bosses claiming that ‘enhanced clearance’ was necessary to reduce the risk of leaves and trees falling on the tracks.


At the time, Network Rail denied the existence of a new programme, saying that its policies had not been altered since 2004. However, the news did prompt government rail minister Jo Johnson to announce that all tree felling works not deemed “safety-critical” would be suspended during the bird nesting season (from March to August), and that the company’s tree felling practices would come under review.


Network Rail maintains that it always tries to balance the needs of the environment with a safe and efficient railway. But why are the works necessary, and why do communities and environmental organisations still smell a rat?

Network Rail claims that incidents caused by vegetation cost the railway more than £100m a year

Leaves on the line

The 1,600 species of plants bedecking the UK’s railways present a unique hassle for rail operators. Network Rail claims that last year, storms, rain and wind caused trees to disrupt its network more than 1,200 times and caused more than 400 instances of trains colliding with fallen trees and large branches. Line-side trees and bushes can obscure signals, get blown onto tracks creating obstacles, or become so overgrown that rail workers have nowhere to stand when trains pass.


Another persistent issue is leaves falling from broadleaf trees onto railway lines. Trains that pass overhead crush them together and fuse a smooth layer of leaves onto the rails. This reduces friction on the track, meaning drivers have to accelerate more slowly and, crucially, have to brake more carefully.


Trees are the root cause of this issue, however one for which the operator is held financially accountable. It claims that incidents caused by vegetation cost more than £100m a year.


Meanwhile, environmentalists are concerned that de-vegetation works are damaging green railway corridors more than they should. Beyond turning pleasant-looking embankments into a barren eyesore, they also disrupt wildlife habitats. Some critics have even called out Network Rail for breaching the Wildlife and Countryside Act, which, among other points, offers basic protections to birds during nesting periods.


“We calculated that every hundred metres of Network Rail’s lines, you have three to four nests in the middle of breeding season,” says Mark Thomas, principal specialist at the Royal Society for the Protection of Birds (RSPB). “You magnify that across the entire network and you’re looking at millions of birds.”


In response to revelations made in May, Bromley Council in Greater London issued tree preservation orders on a group of trees to stop them being destroyed. At the time of writing, an ongoing Change.org petition titled ‘Stop Network Rail Chopping Down Millions of Trees!” has accrued almost 100,000 signatures online.

Covering its tracks

Network Rail insists that it makes efforts to protect, maintain and cultivate the environment on its land. The organisation has used drones to map its railway lines and vegetation stretching 60m either side, which it claims will allow it to target trees that pose a threat. It also hires ecologists to inspect railway corridors before routine maintenance is carried out.


Nevertheless, some environmentalists say the organisation has been prone to slip-ups in the past. Thomas says that over the last 15 years, the RSPB has received calls from communities concerned about the impact of tree felling, which they pass on to the British Transport Police.


“On lots of examples, Network Rail have turned round and said [tree felling is] not essential and they have stopped works which we welcome, but as a charity where our members pay a subscription for us to conserve birds, this is a monumental waste of our money and our time,” says Thomas.


Thomas says that as routine maintenance is often planned in advance, ecologists inspecting potential clearance sites might not identify bird nests that might appear later. Sporadic checks are also made for wildlife during works, but much of the responsibility lies with the contractors, who may not always be able to spot wildlife as effectively, particularly if they are working at night.


In a recent editorial, the Woodland Trust expressed concern that Network Rail’s tree clearance would harm the UK’s overall commitment to deforestation. A document supplied by a Network Rail spokesperson says that the company does not currently “have a fixed target for compensating for tree loss, habitat loss, or changes in biodiversity valuation as a consequence of our maintenance or upgrade work”.

Sporadic checks are also made for wildlife during works, but much of the responsibility lies with the contractors

The Tree Council is working with Network Rail this autumn to trial various alternatives to tree felling, including coppicing and pollarding

 Positive steps 

While the past may not paint a pretty picture of Network Rail’s vegetation management practices, the company’s moves to consult with environmental groups does highlight an effort to improve, according to Tree Council chief executive Sarah Blom.


She says that providing additional training to contractors should be a consequence of the ongoing review, and that trackside workers become “much more focused on ecology, as well as engineers”. She explains that even a simple adjustment in terminology used by contractors – from de-vegging to vegetation management – could promote a healthier attitude.


The Tree Council is working with Network Rail this autumn to trial various alternatives to tree felling, including coppicing and pollarding. These procedures essentially involve cutting trees and shrubs to ground level and giving them the potential to regenerate, instead of the common practice of chemically killing (or plugging) tree stumps.


“I think it would be very helpful to have these trials and to have the scientific evidence that shows that they don’t have to remove as much vegetation as perhaps currently they do,” Blom says. “Let’s do it in a way that there isn't plugging, and recognise that there are some trees at the rail side which are never going to grow and be a hazard, like hawthorn, and so they can be left.”


Thomas agrees, saying that the review will put a greater onus on Network Rail to exert more control over its contractors. He explains that the suspension of works during breeding season sets a good precedent for years to come, as “if there’s no need to do it this season there should be no need in the future”.


Both Blom and Thomas seem optimistic about working more closely with Network Rail in the future to ensure that past mistakes are not repeated, and that a greater balance is struck between keeping the railways safe and creating new avenues for wildlife to flourish.


“What we see is the really big picture, which is they're one of the biggest land owners in Britain and they want to get it right,” says Blom. “If we can work with them then actually it’s a fantastic vein for wildlife going forward, so rather than concentrating on the negative we’re trying to concentrate on the positive and really improve things for the future.”