Extensive Orchards in the Agricultural Landscape: Effective Protection against Fraying Damage Caused by Roe Deer

The objective of this research was to determine the efficiency of different types of protective barriers and how they protect against fraying damage in extensive fruit tree orchards. Orchards in open agricultural land are the target of fraying damage caused by roe deer (Capreolus capreolus L.). We assessed the effectiveness of four protective barriers: a rabbit-proof fence, a standard plastic tube commonly used in forestry, and an innovative plastic tube-variants with and without an additional rendering fat application. The study was situated in three extensive orchards in the southeastern part of Moravia in the Czech Republic. We analyzed the ratio of damaged trees, stem circumference damage, the length and height of damage on tree stems, the time periods with the most observed damage, and finally, the economic efficiency of each studied barrier. Most of the damage was observed in April and July. The most effective protective barrier was the innovative tube with rendering fat application (up to 100%) followed closely by the innovative tube without rendering fat application (95%). The standard plastic tube had an effectiveness of 49%, while the rabbit-proof fence was the least effective at 25%. In terms of the mean damage-lengths on tree stems, we found no significant differences between the rabbit-proof fence and the standard plastic tubes (21-22 cm). The usage of the innovative plastic tube without rendering fat reduced the average damage-length by half (10 cm) as compared to standard types (rabbit-proof fence, standard tube) of protection. The damage-heights on tree stems showed no significant differences among all variants (53-58 cm from the ground). Our analysis of economic parameters showed that rabbit-proof fencing had the worst cost efficiency, while the innovative tubes without rendering fat, had the best cost efficiency. We recommend starting the installation of protective barriers on trees in March, since we recorded relatively high activity of male roe deer in the following months.