In spite of felling, there are always trees growing in forests managed under continuous cover forestry. Many people prefer such forest management over clear cutting. But how do the methods differ in detail?
In the past couple of years, the University has established experimental plots to investigate continuous cover forestry from the perspective of, for example, the carbon sequestration capacity of trees and the living conditions of insect and other animal species.
The plots were established with a donation by Ilkka Herlin to the University of Helsinki in early 2023.
“Plots have been established at the Herlin family farm in Parainen, on the grounds of the University of Helsinki’s Hyytiälä Forest Station, the Evo teaching forest of Häme University of Applied Sciences and in Ruovesi near Hyytiälä on the grounds of the Skogssällskapet foundation,” Professor of Forest Soil Science Jussi Heinonsalo states.
In practice, these are the first such plots in Finland. Four to five separate experimental plots have been established for each site. Each of the plots is further divided into three different forest areas: one for continuous-coverage felling, one for clear-cutting and one left untouched.
“In other words, a limited clear-cutting carried out for research purposes in a recently established plot will take place next to a less comprehensively cut plot under continuous cover management. This way, researchers will be able to compare the immediate effects of different methods on the forest and the rest of the natural environment, such as insects,” Heinonsalo says.
“It’s also important that plots have been established in different locations and in different types of forests. Each location has its specific local conditions that make a difference. We wish to obtain information that is as generally applicable as possible.”
Accessible experimental plots
Researchers from different fields have the opportunity to take advantage of the experimental plots. For example, plant physiologists can investigate the responses of trees to various felling alternatives, while insect specialists can focus on things of interest to them.
“Researchers in many fields have applied for funding for their studies. The donation was allocated to these experimental plots because their establishment is out of reach for individual researchers.”
“Continuous cover forestry is a less intensive felling method for the forest and wildlife. The idea is that the trees in the forest are not all of the same age. Instead, trees of varying ages and sizes grow in the same forest area all the time,” Heinonsalo explains.
In other words, now under investigation is the method’s precise impact on trees, nature and animals compared to clear-cutting.
The continuous coverage plots have been established in forests of different types. This will provide more detailed information on, among other things, the effects of continuous cover forestry on different tree species. The sites were chosen to make them accessible to both researchers and students.
“The locations attract many students, who then have the chance to see the effects of various felling methods with their own eyes.”