411 million m³ of beetle-damaged wood so far
Source: Destatis, BMEL, FHP, BFW, VÚLHM, Czech Forest, Holzkurier estimate (2022–2024) © holzkurier.com
In 2019, damaged wood accounted for over 90%, or 111 million m³, of total logging in Germany, Austria and the Czech Republic in 2019. This was the peak of the bark beetle calamity in Central Europe.
Since then, the volume of damaged wood (damage caused by storms, bark beetles, snowfall and drought) has been decreasing. In 2020, “only” 89 million m³ had been recorded and last year, 62 million m³ were damaged.
The development follows the usual bell curve. Provided the weather conditions are favorable, it can therefore be assumed that a gradual reduction will take place. In Germany, Austria and the Czech Republic, the volume of damaged wood is expected to stabilize at around 40 million m³ a year over the next three years.
Already in 2024, logging will likely approach the average of 88 million m³ of the years 2010 to 2014.
The damage recorded so far is enormous. In the years from 2015 to 2021, 411 million m³ of wood have been damaged. Within ten years (2015-2025), a total of 578 million m³ is expected, since another 170 million m³ will likely accumulate in the coming years, even with favorable weather conditions.
Volume in Germany to halve in 2022
Sources: Destatis, * BMEL, ** Holzkurier estimate © holzkurier.com
Based on initial projections by the nationwide survey on the condition of forests, the German Federal Ministry of Agriculture expects 21 million m³ of damaged wood this year – which would be half the volume recorded in 2021. Last year, it was revised slightly downwards to 40.6 million m³.
The February storms have not been taken into account in the estimate made by the 16 German federal states as of January 1. At 2.1 million m³, hardwood accounts for around 10% of the damaged wood, while the area which needs to be reforested is estimated at 55,000 ha.
3 million m³ of damaged hardwood
Last year, 93% (37.6 million m³) of the damaged wood were softwood and 7% (3 million m³) were hardwood. The area which needs reforestation is estimated at 99,400 ha, compared to 75,600 ha in 2020. In 2020, Germany had reported 66.3 million m³ of damaged wood. 40% of beech, oak and spruce trees show clear crown defoliation – a sign of damage and reduced vitality of the trees. According to the Ministry of Agriculture, however, it is positive that crown defoliation of beech trees has decreased by around 10%.
Stable situation in the Czech Republic
Speaking with the CTK news agency, Czech Minister of Agriculture, Miroslav Toman, quantified the extent of the damage and the log harvest as follows: A total of 25 to 30 million m³ were damaged, and 22 to 25 million m³ were harvested. This means that the volume of damaged wood is exactly at the level reported by the Czech Statistical Office (CZSO) for 2019. However, logging decreased by 5 million m³ compared to the year before, which means that more beetle-infested wood was left in the forests.
Maximum of 20 million m³ in the Czech Republic
Sources: VÚLHM, Czech Forest, Holzkurier estimate (2022–2024) © holzkurier.com
Czech think tank Czech Forest estimates the volume of damaged spruce wood at 15 to 20 million m³ in 2021. This is half of the damage recorded in 2020 and more than ten times the average annual harvest of beetle-damaged wood in the years from 1990 to 2015.
According to estimates by Czech Forest, damage from devaluation, premature and difficult harvest will reach €470 million (CZK 11.7 billion) in 2021. In 2020, around 35 million m³ of damaged wood were harvested, while approximately 4 million m³ had yet to be removed at end of 2021.
Favorable weather in 2021
The main reasons for the decrease in damaged wood is attributed to more favorable weather conditions, which prevented a third generation of bark beetles and improved the vitality of the trees. Furthermore, a large volume of beetle-damaged wood was quickly removed from the forests and new sales opportunities were found.
Based on the analysis of satellite images on www.kurovcovamapa.cz, the areas most affected by the bark beetle calamity in 2021 were the Decin and the Rumburk regions (which border on the Bohemian Switzerland National Park), the Jihlava region and the Trebic region. However, a considerable decrease in logging and periods of drought can be observed.
As for this year, a further decrease in bark beetle infestation and the resulting harvest of damaged wood is expected – unless there are no storms or a severe drought.
25% decrease in Austria
Sources: BFW, FHP, Holzkurier estimate (2022–2024)
In 2021, 1.97 million m³ of bark beetle-damaged log wood were recorded in Austria, which is around 25% less than in 2020. Over the last few years, the situation improved in the hardest hit regions of Lower and Upper Austria, while other regions have seen a massive reproduction of bark beetles.
The five-year average of overall damage caused by biotic and abiotic factors is 8.5 million m³, while an average of 6.5 million m³ of wood have been damaged during the past ten years. In 2021, the volume of wood damaged by beetles, storms and snowfall has thus decreased by 3.3 million m³ or 49% compared to the five- and ten-year average.
Proliferation in the south of Austria
According to the documentation of forest-damaging factors (DWF), half of the federal states (excluding Vienna) saw an increase in beetle-related damage last year.
“On the one hand, damage shifted to areas along and north of the main ridge of the Alps. On the other hand, bark beetles started to proliferate in the south of the country, which was mainly the result of big volumes of wood accumulating after abiotic damage in recent years coupled with high temperatures,” Peter Mayer, head of the Federal Research Center for Forests (BFW), explains.
In Upper and Lower Austria, the volume of beetle-damaged wood halved compared to 2020. Nevertheless, Lower Austria recorded 554,000 m³ of damaged wood, which is the biggest volume of all federal states. In the south, for example in Carinthia and East Tyrol, bark beetles started to proliferate independently of the northern parts of the country and specifically after storm Vaia in 2018 and the snow damage of the two following winters. Protection forests at high altitudes are particularly affected in that part of Austria.
Ongoing drought
Since the winter, low rainfall has led to extreme regional drought, and the winter storms of the past few weeks felled many single and smaller groups of trees. “As a result, we should monitor the bark beetle situation not only in regions with increasing proliferation but, due to the drought, also generally and particularly in those areas where damaged wood has accumulated following windthrow, snowfall or hail events,” BFW forest protection expert Gernot Hoch emphasizes.
