<abstract xmlns="http://www.w3.org/1999/xhtml">
				
				<p> The number of Ips typographus generations developed in a year might be indicative of its population size and of risk to Norway spruce forests. Warm weather and unremoved fallen trees after natural disturbances are thought of as key factors initiating large population increase. We studied I. typographus development in a spruce forest of the Tatra National Park, which was heavily affected by large-scale disturbances in the last decade. Repeated windthrows and consequent bark beetle outbreaks have damaged almost 20,000 hectares of mature Norway spruce forests, what is a half of the National Park forest area. Current I. typographus population size and its response to the environment and to forestry defense measures attract attention of all stakeholders involved in natural resource management, including public. In this paper we analyse the potential I. typographus population size in two consecutive years 2014 and 2015, which represented a climatologically normal year and an extremely hot year, respectively. We used bark temperature and phenology models to estimate the number of generations developed in each year. In 2014, the average bark temperature of standing living trees at study sites was 14.5 °C, in 2015 it increased to 15.7 °C. The bark temperature of fallen logs was 17.7 °C in 2014, and 19.5 °C in 2015. The bark temperature of standing living trees allowed to develop one and two generations in 2014 and 2015, respectively. The elevated bark temperature of fallen logs allowed to develop two generations in 2014 and three generations in 2015. The good match between the predicted and observed timing of each generation emergence as well as the large increase in the number of catches in pheromone traps in 2015 indicated a dramatic increase of the I. typographus population in the extremely warm year, especially at the unmanaged windthrown site.</p>
			</abstract>

The number of Ips typographus generations developed in a year might be indicative of its population size and of risk to Norway spruce forests. Warm weather and unremoved fallen trees after natural disturbances are thought of as key factors initiating large population increase. We studied I. typographus development in a spruce forest of the Tatra National Park, which was heavily affected by large-scale disturbances in the last decade. Repeated windthrows and consequent bark beetle outbreaks have damaged almost 20,000 hectares of mature Norway spruce forests, what is a half of the National Park forest area. Current I. typographus population size and its response to the environment and to forestry defense measures attract attention of all stakeholders involved in natural resource management, including public. In this paper we analyse the potential I. typographus population size in two consecutive years 2014 and 2015, which represented a climatologically normal year and an extremely hot year, respectively. We used bark temperature and phenology models to estimate the number of generations developed in each year. In 2014, the average bark temperature of standing living trees at study sites was 14.5 °C, in 2015 it increased to 15.7 °C. The bark temperature of fallen logs was 17.7 °C in 2014, and 19.5 °C in 2015. The bark temperature of standing living trees allowed to develop one and two generations in 2014 and 2015, respectively. The elevated bark temperature of fallen logs allowed to develop two generations in 2014 and three generations in 2015. The good match between the predicted and observed timing of each generation emergence as well as the large increase in the number of catches in pheromone traps in 2015 indicated a dramatic increase of the I. typographus population in the extremely warm year, especially at the unmanaged windthrown site.

Elevated bark temperature in unremoved stumps after disturbances facilitates multi-voltinism in Ips typographus population in a mountainous forest

Technical University in Zvolen, Faculty of Forestry, T. G. Masaryka 24, SK – 960 53 Zvolen, Slovak Republic

State Forest of TANAP, Tatranská Lomnica, SK – 059 60 Vysoké Tatry, Slovak Republic

Scientica, s. r. o., Hybešova 33, SK – 831 06 Bratislava, Slovak Republic

Institute of Zoology, Slovak Academy of Sciences, Dúbravská cesta 9, SK – 845 06 Bratislava, Slovak Republic

Central European Forestry Journal

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

The number of Ips typographus generations developed in a year might be indicative of its population size and of risk to Norway spruce forests. Warm weather and...

Elevated bark temperature in unremoved stumps after disturbances facilitates multi-voltinism in Ips typographus population in a mountainous forest

Publié en ligne: 03 juin 2016

Pages: 15 - 22

DOI: https://doi.org/10.1515/forj-2016-0002

Mots clés
Norway spruce stands, European bark beetle, bark temperature, PHENIPS, disturbances

© by Peter Fleischer

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Elevated bark temperature in unremoved stumps after disturbances facilitates multi-voltinism in Ips typographus population in a mountainous forest

Publié en ligne: 03 juin 2016

Pages: 15 - 22

DOI: https://doi.org/10.1515/forj-2016-0002

Mots clésNorway spruce stands, European bark beetle, bark temperature, PHENIPS, disturbances

© by Peter Fleischer

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Mots clés
Norway spruce stands, European bark beetle, bark temperature, PHENIPS, disturbances