Moose (Alces alces L.) browsing causes economically significant damage in young Scots pine (Pinus sylvestris L.) stands in Finland. Various methods and devices have been used in attempts to prevent moose damage to Scots pine in young sapling stands. Our aim was to test the effectiveness of birch tar, a new innovation as repellent, under controlled experiments in young Scots pine stands frequently browsed by moose. Experiments were conducted during winter 2007/2008. In experiment A, each of the four experimental stands was divided into two treatments: (1) a treated block where all the top shoots and current-year shoots in the first whorl were treated with birch tar, and (2) an untreated block, i.e. a control area. In experiment B, the effect of birch tar was tested as an odorous repellent, i.e. small sacks with wooden pellets were dipped in the repellent liquid and placed around and inside three young Scots pine stands. In experiment A, there were no differences in the measured stand characteristics and the damage variables between the treated and untreated blocks. In experiment B, no significant differences in the measured variables were found between the protected and control stands. In conclusion, it seems that birch tar does not have a sufficient repellent effect when used against moose browsing.
Bergström, R. & Hjeljord, O. 1987. Moose and vegetation interaction in northwestern Europe and Poland. Swed. Wildl. Res., 1, 213–228.
Cederlund, G., Ljungqvist, H., Markgren, G. & Stålfelt, F. 1980. Foods of moose and roe-deer at Grimsö in central Sweden – results of rumen content analyses. Swed. Wildl. Res., 11, 169–247.
Glöde, D., Bergström, R. & Pettersson, F. 2004. Intäktsförluster på grund av älgbetning av tall i Sverige. Skogforsk, Uppsala, Sweden. Arbetsrapport 570 (in Swedish.)
Gundersen, H., Andreassen, H. P. & Storaas, T. 2004. Supplemental feeding of migratory moose Alces alces: forest damage at two spatial scales. Wildl. Biol., 10, 213–223.
Härkönen, S. 1998. Effects of silvicultural cleaning in mixed pine–deciduous stands on moose damage to Scots pine (Pinus sylvestris). Scand. J. For. Res., 13, 429–436.
doi:10.1080/02827589809383003
Härkönen, S., Heikkilä, R., Faber, W. E. & Pehrson, Å. 1998. The influence of silvicultural cleaning on moose browsing in young Scots pine stands in Finland. Alces, 34, 409–422.
Heikkilä, R. & Härkönen, S. 1993. Moose (Alces alces L.) browsing in young Scots pine stands in relation to the characteristics of their winter habitats. Silva Fenn., 27, 127–143.
Heikkilä, R. & Härkönen, S. 1998. The effects of salt stones on moose browsing in managed forests in Finland. Alces, 34(2), 435–444.
Heikkilä, R. & Härkönen, S. 2000. Thinning residues as a source of browse for moose in managed forests in Finland. Alces, 36, 85–92.
Heikkilä, R. & Löyttyniemi, K. 1992. Growth response of young Scots pines to artificial shoot breaking simulating moose damage. Silva Fenn., 26, 19–26.
Ingemarson, F., Claesson, S. & Thuresson, T. 2007. Costs and Benefits of Moose and Roe Deer Populations. Skogsstyrelsen, Jönköping, Sweden. Rapport 3 (in Swedish with English summary).
Lavsund, S. 1987. Moose relationships to forestry in Finland, Norway and Sweden. Swed. Wildl. Res., 1, 229–244.
Lindqvist, I., Lindqvist, B., Setälä, H. & Tiilikkala, K. 2006. Birch oil repels slugs and snails. In AFPP – Third International Conference on Non Chemical Crop Protection Methods. Lille, France, 13, 14 and 15 March 2006, pp. 769–775. Abstracts. CD-ROM.
Löyttyniemi, K. & Lääperi, A. 1988. Moose in Finnish Forestry. University of Helsinki, Department of Agricultural and Forest Zoology. Report 13 (in Finnish with English summary).
Löyttyniemi, K., Heikkilä, R. & Repo, S. 1992. Pine tar in preventing moose browsing. Silva Fenn., 26, 187–189.
Månsson, J., Andrén, H., Pehrson, Å. & Bergström, R. 2007. Moose browsing and forage availability: a scale-dependent relationship? Can. J. Zool., 85, 372–380.
doi:10.1139/Z07-015
Neff, D. J. 1968. The pellet-group count technique for big game trend, census, and distribution: a review. J. Wildl. Manage., 32, 597–614.
doi:10.2307/3798941
Pasanen, T. 2006. Koivutisle lehtokotiloiden (Arianta arbustorum) karkotteena ja sen käytön ympäristövaikutukset maaperässä ja vesieliöissä. Unpublished Graduate thesis, University of Helsinki.
Senft, R. L., Cougehenour, M. B., Bailey, D. W., Rittenhouse, L. R. & Swift, D. M. 1987. Large herbivore foraging and the ecological hierarchies. Bioscience, 37, 789–799.
doi:10.2307/1310545
Torvelainen, J. 2007. Multiple-use forestry. In Finnish Statistical Yearbook of Forestry 2007 (Peltola, A., ed.), pp. 201–218. Agriculture, Forestry and Fishery 2007. Finnish Forest Research Institute.
