I have a broad interest in plant protetion research. My research has mainly focused on insect pests in forests. I have eg worked with plant protection against the pine weevil Hylobius abietis.
In my licentiate thesis I have studied the flight pattern and the effect of temperature on flight activity and development of the spruce bark beetle (Ips typographus) in southern Sweden. In a current project I am studying the effects of climate change on the phenology of bark beetles.
Forest entomology, Sverigeresan söder (SG0188)
The EU-project WeevilSTOP were also Oslo University and Teknologisk Institutt in Norway is included.
How is climate change affecting the spruce bark beetle and the larger pine shoot beetle? (Funded by Brattåsstiftelsen)
The spruce bark beetle and the larger pine shoot beetle are two of the most serious forest pests. We have in recent years observed earlier flight in spring. With the help of not only historical data from the literature, but also a very extensive unpublished data for these species, we want to clarify how the flight initiation changed over time, how the conditions for sister brood flight and two generations per year has changed and what consequences this will have for the forestry sector. How the situation will appear in different future climate scenarios will be simulated based on the measured changes. (In collaboration with Niklas Björklund, and Anna-Maria Jönsson (Lunds universitet) )
Öhrn, P. (2012). Seasonal flight patterns of the Spruce Bark Beetle (Ips typographus) in Sweden -Phenology, Voltininsm and Development. Department of Ecology. Uppsala, Swedish university of agricultural sciences. Licentiate thesis: p. 42 [PDF]
Öhrn, P., Långström, B., Lindelöw, Å., Björklund, N. (2014) Seasonal flight patterns of Ips typographus in southern Sweden and thermal sums required for emergence. Agriculture and Forest Entomology.
Published on-line 5 JAN 2014
[ARTICLE] [Open access manuscript version]
Ylva Persson, Rimvydas Vasaitis, Bo Långström, Petter Öhrn, Katarina Ihrmark and Jan Stenlid. 2009. Fungi Vectored by the Bark Beetle Ips typographus Following Hibernation under the Bark of Standing Trees and in the Forest Litter. Microbial Ecology 58:651-659.
Långström, B., Lindelöw, Å., Schroeder, M., Björklund, N. & Öhrn, P. 2009. The spruce bark beetle outbreak in Sweden following the January-storms in 2005 and 2007. In: Kunca, A. Zubrik, M. (eds.) Insects and Fungi in Storm Areas. Proceedings of the IUFRO Working Party 7.03.10 Methodology of Forest Insect and Disease Survey in Central Europe from the workshop that took place on September 15 to 19, 2008 in Štrbské Pleso, Slovakia, p.13-19.[PDF]
Öhrn P., Matthew K., Gareth H., Björklund N. 2008. Two non-destructive techniques for determining the sex of live adult Hylobius warreni. The Canadian Entomologist vol 140 nr 5 617-620
Öhrn, P. Changes in phenology of bark beetles in response to climate change, Invited keynote speaker on BaltDendro 22-25 Aug 2016,Annas Koku Skola, Riga, Latvia.
Öhrn, P. Lindelöw, Å. Långström, B. 2012. Flight activity of the ambrosia beetles Trypodendron laeve and Trypodendron lineatum in relation to temperature in southern Sweden. In: Delb, H. Pontualli, S. (eds.) Biotic Risks and Climate Change in Forests 10th IUFRO Workshop of WP 7.03.10 “Methodology of Forest Insect and Disease Survey in Central Europe”, September 20-23 2010 in Freiburg, Germany.[PDF]
Öhrn, P. & Långström, B. 2009. Flight activity and development of the spruce bark beetle Ips typographus in southern Sweden. Poster presented at the IUFRO Conference Forest Insects and Environmental Change organized by Working Party 7.03.05: Integrated Control of Scolytid Bark Beetles and Working Party 7.03.07: Population Dynamics of Forest Insects on 27 September – 2 October 2009 at Jackson Hole, Wyoming, USA.
Öhrn, P., Långström, B. & Björklund, N. 2009. Flight activity of the spruce bark beetle Ips typographus in southern Sweden (poster abstract) In: Kunca, A. Zubrik, M. (eds.) Insects and Fungi in Storm Areas. Proceedings of the IUFRO Working Party 7.03.10 Methodology of Forest Insect and Disease Survey in Central Europe from the workshop that took place on September 15 to 19, 2008 in Štrbské Pleso, Slovakia, p.148
Vasaitis, R., Persson, Y., Långström, B., Solheim, H., Ihrmark, K., Öhrn, P. and Jan Stenlid. 2008. Ceratocystis polonica and other fungi vectored by Ips typographus in forest areas of south Sweden following storm disturbance. Oral presentation at the IUFRO Conference Insects and Fungi in Storm Areas organized by the IUFRO WG 7.03.10 "Methodology of Forest Insect and Disease Survey in Central Europe" on September 15 to 19, 2008 in Štrbské Pleso, Slovakia.
Öhrn, P, Björklund, N, Lindelöw, Å., Långström, B. (2012) Ta ut vindfällda granar i rätt tid. SkogsEko, 4, p. 43.[FULL TEXT]
Långström, B. & Öhrn, P. 2009. Rapport om barkborrarnas aktivitet och utveckling under 2009 på försöksplatserna Asa, Tönnersjöheden, Gammalstorp och Remningstorp. Rapport till Skogsstyrelsen 2009-12-15.
Öhrn, P. 2007. Granbarkborrars utveckling i barkskavd massaved. Rapport till Södra. 2007-10-27.
Öhrn, P. 2006. Effekten av metyljasmonat som skydd mot gnag av snytbagge (Hylobius abietis) på gran- och tallplantor. Dept. of entomology, SLU. Examensarbete i entomologi vol. 2006:1.