Starting from May, Metsä Group's contract entrepreneurs will use the Phlebiopsis gigantea fungus for stump treatment and biodegradable oil to lubricate harvesters' saw chains. The changes will support Metsä Group's goals of regenerative forestry and reduce fossil carbon dioxide emissions from harvesting.

Harvesters have similar guide bars and saw chains to those found in chainsaws. The saw chains require lubrication. Starting from May, Metsä Group's contract entrepreneurs will only use vegetable oil-based or synthetic and biodegradable chain oils instead of the currently used fossil oils.

Harvesters apply an agent on freshly cut stumps, which prevents rot fungi spreading through the stump and roots into the ground and the surrounding living trees. Urea is commonly used as a treatment agent. Its production involves the use of natural gas. Urea causes carbon dioxide emissions when dissolving. Stump treatment is required when the average diurnal temperature is above 0 °C.

In May, Metsä Group's contract entrepreneurs will begin using the biological and organic Rotstop product for stump treatment. The product contains Phlebiopsis gigantea, which will start growing in the stump, preventing rot spreading into the stump. The use of Phlebiopsis gigantea as a biological protection method is based on competition between species. Switching to this method in root rot control is favourable to the living conditions of species occurring and propagating in sawn stumps. Urea is limited to use only during late autumn frosts, to avoid freezing damage to the stump treatment equipment.

Introducing plant-based oils and biological control methods in forestry work implements Metsä Group's environmental goals. The goal of regenerative forestry is to enhance the state of biodiversity. Metsä Group also aims to reduce fossil emissions from wood supply by 30 per cent by 2030.

"We want to improve the state of environment by using more environmentally friendly products while reducing our fossil carbon dioxide emissions. According to our estimate based on our harvesting volumes, discontinuing the use of urea will reduce the carbon dioxide emissions from our harvesting operations by an amount corresponding to the annual emissions of 1,100 diesel cars. Annually, more than half a million litres of fossil chain oil will no longer be used in the forests," says Hannu Alarautalahti, SVP, Production, Metsä Group.

Metsä Group has ensured with the producer of Rotstop that enough of the product is available to Metsä Group's entrepreneurs. Plant-based and synthetic biodegradable chain oils are widely available, and their suitability has been ensured through usability tests.