A clear-cut by the FSC-certified forest company Holmen in Hälsingland, Sweden. Photo: Robert Svensson

The Swedish forest worker and conservationist Bert Andersson has written an opinion article about damage caused by forest machines to the forest floors in Sweden. Bert Andersson passed away in 2016 but his words are still very relevant. He lived in the forest his whole life and experienced how the forest landscape changed from old-growth forests full of biodiversity to barren landscapes with damaged forest floors.

This is a translated article, previously published in Hela Hälsingland.

Damage caused by forestry machines emerged when the first forwarders appeared in the Swedish forest, about 50 years ago. The forwarders are built specially to manage driving with heavy timber loads in difficult terrain. Every year the machines have become larger, heavier and have stronger engines with technical solutions which have led to extreme navigation ability in the forest but at the cost of severe damage to the forest floors.

No human activity causes such severe and extensive damage to the forest floors as the forestry machines. It will take hundreds of years- or even thousands of years, depending on the soil and its location, before the wheel tracks, which are often over one meter deep, grow back together again. During this long time lapse the damages continue causing serious impact to nature and climate.

In areas where damage to the forest floor is severe there is a significant change in hydrology and soil chemistry which leads to leaching of humus, nutrients and very poisonous methylmercury. 20 per cent of all methylmercury that ends up in lakes and water are estimated to come from forestry. Of course, this leads to negative impacts to the soil, to water and to biodiversity. Deep tracks running down slopes cause erosion so that enormous amounts of sludge end up in the surroundings, sometimes up to half a kilometer away. After a forest has been logged a machine prepares the ground with a ploughing effect which completes the massacre.

There is a lot of talk about how important it is to limit emissions of carbon dioxide because of temperature rise and climate problems. From clear-cuttings and soil damage caused by machines the CO2 is literally shooting out into the atmosphere. Even if planted trees will absorb carbon it is not sure that there is enough time for the forest to become carbon neutral since the trees today are logged whilst they still are young.

Lakes and streams receive a lot of organic material from loggings and soil damage. When the organic material ends up in water and is decomposed it turns into methane gas. According to research methane is a 30 to 35 times stronger greenhouse gas than carbon dioxide and will therefore lead to much faster warming.

If the politicians are serious about environmental politics and wish to leave a society for the next generation where the great environmental issues are solved, they must urgently legislate against forestry’s deviations and the increasing damage to forest floors. The consequences of the soil damage are dangerous and unmanageable. Instead of being solved, the environmental problems in forestry are getting worse.

By Bert Andersson, forest worker