DOI: 10.5061/dryad.4f4qrfjmr
title: Data from: Debarking harvesters simultaneously combat the European spruce bark beetle Ips typographus and conserve non-target beetle diversity

description: In the face of climate change, the European Spruce Bark Beetle (Ips
 typographus) breeding predominantly in Norway spruce (Picea abies) led to
 exceptional amounts of damaged timber in European forests. Up to now, if
 pest control is applied, damaged or weakened P. abies trees are either
 extracted by salvage logging or, when quantities are low, made unsuitable
 for breeding by manual debarking techniques. Both pest control
 interventions are costly, are often limited by the short timeframe of
 effectiveness and come with negative impacts on the non-target
 biodiversity. As alternatives for timely removal, a debarking head for
 harvesters for large scale disturbances and a bark gouging device for
 motor-manual treatment have been developed in recent years to make
 breeding material unsuitable for bark beetles and reduce existing larvae.
 Based on data from an experimental design with infested Norway spruce
 logs, we show that the harvester debarking head and the motor-manual bark
 gouging regulate I. typographus populations efficiently, whereas a
 conventional harvester did not reduce the emerging bark beetles. Species
 assemblages of non-target beetles living in the infested Norway spruce
 logs were altered from the natural species assemblages in control logs by
 processing logs with the debarking head or the bark gouging device but not
 by the conventional harvester. None of the bark treatments reduced
 non-target beetle species richness in this experiment. We endorse the
 debarking head and bark gouging as alternatives to salvage logging and
 manual debarking. This uncouples pest control from in-time dependencies on
 the availability of transport capacities. Further, the debarking head and
 bark gouging open up the opportunity to retain dead wood biomass in the
 forest, supporting ecological benefits and conservation goals.
 Particularly for protected areas these two new management option better
 balance requirements of pest control and biodiversity conservation.
description: The study was conducted in the buffer zone of the Bavarian Forest
 National Park, where active bark beetle interventions are implemented (N
 49° 5' 13'' E 13° 14' 0'').<em>
 </em>Forest stands in this area are dominated by <em>P.
 abies</em> and have experienced extensive <em>I.
 typographus</em> outbreaks in the past. Sixteen <em>P.
 abies</em> trees of similar size, age and with signs of early
 colonization (white larval stage without teneral beetles)<em>
 </em>by <em>I. typographus </em>were felled in June
 2020<em>. </em>All trees met the criteria for removal of the
 regulations for the buffer zone management and were randomly assigned in
 groups of four trees to each of the treatments, to account for potential
 differences in colonization densities between trees. The control trees
 were felled without any further bark manipulation. After felling,
 delimbing, and cutting into sections, the second group was treated with
 the bark gouging device attached on a conventional chainsaw
 (“Streifenmesser Nationalpark Bayerischer Wald”, EDER Maschinenbau GmbH,
 Wolfenbüttel, Lower Saxony, Germany). Another group of four trees was
 felled and processed with a harvester fitted with a conventional
 aggregate, representing the effect to logs from salvage logging and
 extraction operations. The last group was debarked using a John Deere 1270
 G 8-wheel harvester in combination with a H 480 C debarking head, refitted
 with 4 debarking rolls and a Eucalyptus measuring wheel.The bark was
 completely removed by passing over the logs multiple times.
 From each log, three segments, measuring 70 cm, were cut out at
 random locations to account for differences of colonization densities
 within the logs. Then, the 48 segments (12 per treatment) were placed in
 rearing barrels to collect abundances of all emerging arthropods from June
 until October 2020. All beetle species were separated from other
 arthropods and identified to species level by taxonomic expert Andreas
 Weigel.
description: # Debarking harvesters simultaneously combat the European spruce bark
 beetle (*Ips typographus*) and conserve non-target beetle diversity
 [https://doi.org/10.5061/dryad.4f4qrfjmr](https://doi.org/10.5061/dryad.4f4qrfjmr) We compared different methods of mechanical bark treatments for the regulation of *Ips typogrpahus* populations in freshly cut and colonzed spruce logs and their effect on non-target beetle diversity. From each log, three segments, measuring 70 cm, were cut out at random locations to account for differences of colonization densities within the logs. The 48 segments (12 per treatment) were placed in rearing barrels to collect abundances of all emerging arthropods from June until October 2020. All beetle species were separated from other arthropods and identified to species level by taxonomic expert Andreas Weigel. The four treatments were: Control (K), conventional Harvester (NH), bark gouging (PS) and Harvester Debarking Head (DH) Results: The harvester debarking head and the motor-manual bark gouging regulate I. typographus populations efficiently, whereas a conventional harvester did not reduce the emerging bark beetles. Species assemblages of non-target beetles living in the infested Norway spruce logs were altered from the natural species assemblages in control logs by processing logs with the debarking head or the bark gouging device but not by the conventional harvester. None of the bark treatments reduced non-target beetle species richness in this experiment. ## Description of the data and file structure Dataset of emerging beetle species abundances from the experimental logs. The **sample** column defines treatment and segment number. The column **species** indicates the species name, while **count** provides the abundance count from each segment and species.