Browsing deterrent and phytotoxic effects of roe deer repellents on Pinus sylvestris end Picea abies seedlings

The abilities of eight repellents to reduce browsing damage by roe deer (Capreolus capreolus) were tested on 2-year-old containerized seedlings of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies L.) in two field tests. The study was performed on 10 773 seedlings on 17 newly planted clearcuts in southern Sweden. The frequencies of untreated pine and spruce seedlings that had been browsed were 31% and 37%, respectively, in the first test performed during the winter of 1991-1992. In the second test, performed in the winter of 1992-1993, the frequency of browsing among untreated spruce seedlings was 70%. Gyllebo Blood meal, Gyllebo Seedling Protection, Gyllebo Granulate, I.A.-Game Repellent, Cervacol Extra, freeze tape, fish oil and Dendrocol Extra showed significant deterrent effects. Anipel had no significant deterrent effect at the recommended dose. Anipel, fish oil, Gyllebo Blood meal and Cervacol Extra caused significant phytotoxic effects. The results of these tests should help in deciding which repellents are worth testing at a larger scale or are worthy of further development.