The Finnish Natural Heritage Foundation has protected a forest ravaged by a thunderstorm in Hannusranta in Kajaani. The conservation area, which was named Paatsamakorpi, was hit by a strong downburst in June 2020, which left the forest with hundreds of cubic metres of windthrow. The moist mixed forest is over a hundred years old and now covers over 10.5 hectares.
“For forest owners, windthrow often causes economic loss. But for nature, it is like winning the lottery. The fallen tree begins to decay, which makes it the perfect home for countless forest organisms such as beetles, bracket fungus and moss,” explains Ari-Pekka Auvinen, Conservation Officer at the Finnish Natural Heritage Foundation.
The Paatsamakorpi forest was bought from private sellers through two separate deals. The larger of the areas was sold by Petri and Pekka Manninen, father and son, who run a forestry services business and are well acquainted with the different kinds of value forests can offer.
“We were already in negotiations with the Finnish Natural Heritage Foundation about selling the forest before the storm damage occurred. Once the wind got involved, the matter was settled on both sides. Clearing the trees and renewing the forest would have taken considerable effort. It was better to let this part of Hannusranta’s extensive windthrow become a paradise for organisms that live in decayed trees,” Pekka Manninen states.
In future, the forest structure of Paatsamakorpi will diversify quickly. In just a few years the fallen trees will decay enough to allow the next generation of trees, which has been waiting for its turn on the forest floor, to take over. Hannusranta’s old buckthorn and its alder, which is rare in the Kajaani region, will gain more living space in the middle of the storm-damaged trees.
“It will be fascinating to observe how nature’s processes will change Paatsamakorpi in the future,” Ari-Pekka Auvinen says.
Paatsamakorpi is the Finnish Natural Heritage Foundation’s ninth conservation area in Kainuu.