DOI: 10.5061/dryad.k6t16
title: Data from: Alien and native plant establishment in grassland communities is more strongly affected by disturbance than above- and below-ground enemies

description: Understanding the factors that drive commonness and rarity of plant
 species and whether these factors differ for alien and native species are
 key questions in ecology. If a species is to become common in a community,
 incoming propagules must first be able to establish. The latter could be
 determined by competition with resident plants, the impacts of herbivores
 and soil biota, or a combination of these factors. We aimed to tease apart
 the roles that these factors play in determining establishment success in
 grassland communities of 10 alien and 10 native plant species that are
 either common or rare in Germany, and from four families. In a two-year
 multisite field experiment, we assessed the establishment success of seeds
 and seedlings separately, under all factorial combinations of low vs. high
 disturbance (mowing vs mowing and tilling of the upper soil layer),
 suppression or not of pathogens (biocide application) and, for seedlings
 only, reduction or not of herbivores (net-cages). Native species showed
 greater establishment success than alien species across all treatments,
 regardless of their commonness. Moreover, establishment success of all
 species was positively affected by disturbance. Aliens showed lower
 establishment success in undisturbed sites with biocide application.
 Release of the undisturbed resident community from pathogens by biocide
 application might explain this lower establishment success of aliens.
 These findings were consistent for establishment from either seeds or
 seedlings, although less significantly so for seedlings, suggesting a more
 important role of pathogens in very early stages of establishment after
 germination. Herbivore exclusion did play a limited role in seedling
 establishment success. Synthesis: In conclusion, we found that less
 disturbed grassland communities exhibited strong biotic resistance to
 establishment success of species, whether alien or native. However, we
 also found evidence that alien species may benefit weakly from soilborne
 enemy release, but that this advantage over native species is lost when
 the latter are also released by biocide application. Thus, disturbance was
 the major driver for plant species establishment success and effects of
 pathogens on alien plant establishment may only play a minor role.
description: Data_Müller et al. 2016
 Journal of EcologyData on survival of
 seedlings collected in the field (Müller et al. 2016). Columns: Individual
 (Identifier for site/plot/xyposition of each individual); Site (column for
 site); Plot (column for plot); Position (column for Position); Disturbance
 (disturbance treatment high/low); Fungicide (Biocide application yes/no);
 Herbivory (open / closed cage); Family (species family); Genus (species
 genus); Species (species name); Name(alternative abrev. for species
 names); Origin (alien/native); Commonness (common/rare); Grid_cells
 (number of grid cells occupied by the species in Germany); Planted
 (planting date); t_cover(date when veg. cover was recorded for the
 respective position); t1 (time of 1st survey); Survival_t (recorded
 survival yes/no 1st survey); Height_t1 (recorde plant height 1st survey);
 Leaves (recorded leaves 1st survey); t2 (time of 2nd survey); Survival_t2
 (survival at 2nd survey); t3 (time of 3rd survey); Survival t3 (survival
 at 3rd survey); t4 (timing of 4th survey); dayst4_t1 (number of days
 between survey 1 and 4); Survival t4 (survival at 4th survey):
 Height_t4(plant height at 4th survey); Leaves_t4 (recorded leaves at
 survey4); t5 (time of 5th survey); Survival_t5 (survival at 5th survey);
 height_t5 (recorded plant height at t5); Leaves _t5(recorded leaves at 5th
 survey); forbs (fraction of forb cover); grass (fraction of grass cover);
 background (fraction of bare ground)Müller et al. 2016
 Journal of Ecology (2) seedsData for establishment
 from seeds collected in the field for Müller et al. 2016. Columns: site
 (codes for the respective site); plot (codes for the respective plot in
 site); fungicide (biocide treatment yes/no); disturbance (disturbance
 treatment yes/no); x (x position within plot); y (y position within plot);
 species (species name); name (alternative coding for species names);
 origin (alien /native); Commonness (common/rare); tk25 (number of grid
 cells occupied in Germany); Family (species family); seedlings (number of
 seedlings recorded in the field); sowing density (initial number of seeds
 sown in the field at the respectie position) Müller et al. 2016 Journal of
 Ecology (2) seeds.xls