Articles by Helena Haakana

In Fennoscandia, moose (Alces alces L.) browsing significantly damages commercial forests, influencing tree species composition and seedling growth. We examined the long-term development of moose-damaged forests in Finland, focusing on seedling stands artificially regenerated for Scots pine (Pinus sylvestris L.). The analysis used National Forest Inventory (NFI) data from four consecutive five-year periods (2004–2023). Remeasured permanent sample plots were used to compare the development of damaged and undamaged stands. The total area affected by moose increased from 0.966 to 1.116 million hectares over the four NFI cycles. Of this, 61% was significantly damaged, indicating reduced silvicultural quality, and the proportion was higher in the north. Among young seedling stands recorded in the first inventory as being artificially regenerated for Scots pine, moose damage affected 44% of their total area nationwide over the study period, with a higher proportion in the south. Moose browsing frequently shifted the dominant tree species from Scots pine to downy birch (Betula pubescens Ehrh.) and, secondarily, Norway spruce (Picea abies (L.) H. Karst.). Where notable or severe damage was observed in the first inventory, crop seedling numbers remained lower throughout the study. Our findings show that moose browsing has long-term effects on tree species composition and stand structure, including mean height, mean diameter, and density. Damage patterns vary regionally and by stand characteristics, although many previously affected stands show recovery or reduced impacts. Large-scale monitoring systems such as NFIs provide long-term data for detecting changes in browsing intensity and vegetation, thereby supporting forest and wildlife management.

• Haakana, Natural Resources Institute Finland (Luke), P.O. Box 2, FI-00791 Helsinki, Finland https://orcid.org/0000-0002-4830-800X E-mail: helena.haakana@luke.fi
• Matala, Natural Resources Institute Finland (Luke), Yliopistokatu 6, FI-80100 Joensuu, Finland https://orcid.org/0000-0002-5867-5057 E-mail: juho.matala@luke.fi
• Huuskonen, Metsähallitus, Forestry Ltd. P.O. Box 80, FI-00521 Helsinki, Finland E-mail: saija.huuskonen@metsa.fi
• Korhonen, Natural Resources Institute Finland (Luke), Yliopistokatu 6, FI-80100 Joensuu, Finland https://orcid.org/0000-0002-6198-853X E-mail: kari.t.korhonen@luke.fi
• Nikula, Natural Resources Institute Finland (Luke), Ounasjoentie 6, FI-96200 Rovaniemi, Finland https://orcid.org/0000-0001-8372-8440 E-mail: ari.nikula@luke.fi
• Räty, Natural Resources Institute Finland (Luke), P.O. Box 2, FI-00791 Helsinki, Finland https://orcid.org/0000-0001-9898-8712 E-mail: minna.raty@luke.fi

In 2019–2023 the 13th Finnish National Forest Inventory (NFI) was implemented by measuring a total of 62 266 sample plots across the country. The methodology of the sampling and measurements was similar as in the previous inventory, but the proportion and number of remeasured permanent plots was increased to improve the monitoring of annual increment and other changes in the forests. Only 6.2 M ha (14%) of Finland’s total land area (30.4 M ha) is other land than forestry land. Productive and poorly productive forests cover 22.9 M ha (75%) of the total land area.  The forest area has remained stable in recent decades but the forest area available for wood supply (FAWS) has decreased due to increased forest protection – 23% of the forestry land and 10% of the productive forest are not available for wood supply. Compared to the previous inventory, forest resources have continued to increase but the average annual increment has declined from 107.8 M m³ to 103.0 M m³. The quality of forests from the timber production point of view has remained relatively good or improved slightly. The area of observed forest damage on FAWS is 8.4 M ha (46% of FAWS area), half of these minor damages with no impact on stand quality. Although the area of forest damage has not increased, the amount of mortality has continued to increase, and is now 8.8 M m³ year^–1. The amount of dead wood has continued to increase in South Finland, while in North Finland the declining trend has turned into a slight increase. Since the 1920s, the area of forestry land has remained stable, but the area of productive forest has increased due to the drainage of poorly productive or treeless peatlands. The total volume of growing stock has increased by 84% and annual increment has more than doubled.

• Korhonen, Natural Resources Institute Finland (Luke), P.O.Box 68, FI-80100 Joensuu, Finland https://orcid.org/0000-0002-6198-853X E-mail: kari.t.korhonen@luke.fi
• Räty, Natural Resources Institute Finland (Luke), P.O.Box 2, FI-00790, Helsinki, Finland https://orcid.org/0000-0001-9898-8712 E-mail: minna.raty@luke.fi
• Haakana, Natural Resources Institute Finland (Luke), P.O.Box 2, FI-00790, Helsinki, Finland E-mail: helena.haakana@luke.fi
• Heikkinen, Natural Resources Institute Finland (Luke), P.O.Box 2, FI-00790, Helsinki, Finland https://orcid.org/0000-0003-3527-774X E-mail: juha.heikkinen@luke.fi
• Hotanen, Natural Resources Institute Finland (Luke), P.O.Box 68, FI-80100 Joensuu, Finland E-mail: juha-pekka.hotanen@luke.fi
• Kuronen, Natural Resources Institute Finland (Luke), P.O.Box 2, FI-00790, Helsinki, Finland https://orcid.org/0000-0002-8089-7895 E-mail: mikko.kuronen@luke.fi
• Pitkänen, Natural Resources Institute Finland (Luke), P.O.Box 68, FI-80100 Joensuu, Finland https://orcid.org/0000-0002-7583-6297 E-mail: juho.pitkanen@luke.fi