DOI: 10.5061/dryad.8sf7m0cww
title: The demise of enemy release associated with the invasion of specialist folivores on an invasive tree

description: There is a long history of humans either intentionally or accidentally
 moving plant species to areas outside of their native ranges. In novel
 environments, populations of many of these plant species exhibit explosive
 population growth and spread, in part due to the absence of coevolved
 enemies such as herbivorous insects. However, over time such enemies can
 “catch-up” with their host and re-establish host-herbivore relationships.
 Though this phenomenon has been documented in several systems, little
 evidence exists on how this re-assembly of enemies results in increased
 levels of herbivory. In this study we focus on the case of black locust
 (Robinia pseudoacacia), a sparsely populated tree species when growing on
 undisturbed sites in its limited native range in the eastern United States
 but a highly invasive species, especially in disturbed environments, in
 most temperate world regions. We recorded folivore damage on invasive
 populations in five continents, including both native and invaded portions
 of North America. Here, we investigated i) how total foliage damage and
 damage caused by different groups of folivores differs among regions; ii)
 how seasonal development of folivore damage differs among regions; iii)
 how folivory varies with distance from the native range within North
 America; and iv) how the number of recorded specialist folivores
 correlates with the amount of folivory. We observed strong differences
 among regions in the amount and type of folivore damage, with the native
 range experiencing the highest damage, especially that caused by the
 native chrysomelid beetle Odontota dorsalis, which is limited to the
 native and invaded North American range of R. pseudoacacia. Among world
 regions, total folivory is negatively associated with the distance from
 the native range and positively associated with the number of established
 R. pseudoacacia specialist folivore species, supporting the hypothesis
 that global patterns of herbivore invasions are associated with diminished
 enemy release.
description: # The demise of enemy release associated with the invasion of specialist
 folivores on an invasive tree
 ## Description of the data
 and file structure -        **Ecography_script.zip - **R script of used
 statistical analyses with corresponding CSV files. -       
 **Medzihorsky_eal_2024_Raw_data.xlsx – **MS Excel file of leaf damage
 estimates for every location. Variables: **CountryII:** CA - Canada; CZ –
 Czech Republic; JP – Japan; US – USA invaded range of *Robinia
 pseudoacacia*; US* - USA native range of *R. pseudoacacia*; NZ – New
 Zealand, SA – South Africa **Locality:** name of closest city/town to
 sampled locality **Year:**  year of sampling **Date:** date of samling;
 DD_MM_YY **date_ID:** number of the day in the year (1 - 365); integer
 **date_ID_comp:** number of the day in the year with correction for
 Southern Hemisphere (applies only for New Zealand and South African
 localities); date_ID + 183; after exceeding 365 starts from 1) **Tree**:
 number of the tree on locality; integer **Leaf**: number of the leaf on
 the tree; integer **ID_tree**: identification code of a tree; CountryII +
 Locality + Year + Tree **ID_tree_date**: ID_tree + date_ID_comp
 **ID_leaf**: identification code of a leaf; ID_tree_date + Leaf
 **No_leaflets**: number of leaflets on the samled leaf; integer **TDA**:
 total damaged area; sum of recorded damage by different groups of
 folivores; expressed in % **Freefeeders**: damage by free feeding
 folivores; expressed in % **Skelotonizers**: damage by skeletonizers;
 expressed in % **Other_leafminers**: damage by other leafmining insects;
 expressed in % **Odontota_lar**: leaf-mining damage by larval *Odontota
 dorsalis*; expressed in % **Gallmakers**: damage by galling insects;
 expressed in % -        **Robinia_scans.zip – **photographic material of
 leaves evaluated for this study. Robinia_scans. zip contains photographic
 material of R. pseudoacacia leaves which were evaluated for damage and
 recorded into the Medzihorsky_eal_2024_Raw_data.xlsx MS Excel file. The
 data was pivoted and used for statistical analyses using the scripts in
 Ecography_script.zip. All the information on packages used are in the
 Materials and Methods section of the manuscript. Coordinates of the
 localities are listed in the Supporting Information. ## Code/Software All
 data preparation and analyses were performed using the R language and
 packages and described in the Materials and Methods section of the
 manuscript.