Mass tree-planting can be damaging

Tree planting on a mass scale in the United Kingdom could cause more harm than good to the environment if not planned properly, a report warns.

An independent advisory committee warns the UK government it must approach its net zero carbon targets for 2050 carefully, with a joined-up policy on interventions that do not inadvertently lead to higher emissions.

According to the Natural Capital Committee, or NCC, guidance, the government's pathway to reaching net zero emissions must involve a "wide range of nature-based interventions".

The new advice document says that increased tree planting without careful planning is likely to lead to the loss of other habitats and land uses, including species rich grasslands, heathlands and peatlands, particularly where these are in a degraded state.

The NCC advice on reaching the net zero target warns that badlyplanned tree planting would only increase greenhouse gas output.

It warns that planting trees in peat bogs would prove a mistake, as peat locks up vast quantities of carbon — but trees dry out peat. This can release more greenhouse gases than the trees absorb, it said.

NCC member Ian Bateman, from the University of Exeter, said: "The mantra has to be 'the right tree in the right place'.

"We would be crazy to undertake the massive scale of planting being considered if we did not also consider the wider effects upon the environment including impacts on wildlife, benefits in terms of reducing flood risks and effects on water quality, improvements to recreation and so on."

The report adds that filling grasslands with trees would reduce the UK's ability to produce meat — which may lead to increasing imports from places that produce beef by felling rainforests.

The report also says there is little point closing polluting UK factories if the country then imports goods from places with worse emissions.

It notes that huge publicity has been given to the UK's plans for planting 11 million trees to lock up carbon emissions, but they warn that conserving carbon in soils is equally or more important.

The report points to Office for National Statistics estimates that in 2007 UK soils contained 94.2 percent of the total stock of biological carbon — excluding fossil fuel carbon.

It says soil degradation through erosion, intensive farming and development creates losses estimated at between 0.9–1.4 billion pounds ($1.1-1.7 billion) per year for England and Wales alone. NCC member Kathy Willis, from Oxford University, told BBC News: "We love looking at trees — we get all these positive emotions, smells and sounds — but most of us don't look at soil that actually underpins everything."