DOI: 10.5061/dryad.2ngf1vhz5
title: Home sweet home: Evaluation of native versus exotic plants as resources for insects in urban green spaces

description: Insect decline and loss of biodiversity not only affect large-scale
 agricultural landscapes but are increasingly recognized in urban
 environments. It is undisputed that a greater supply of flowers in urban
 green spaces can provide insects with more food and habitat. However,
 controversy still surrounds the question of whether native wild plants or
 non-native ornamental plants and varieties are the right choice. The aim
 of our study was to investigate the number of insects interacting with
 different types of plants: twelve ornamental and six related wild
 perennials. In this context, not only the number of flower visitors was
 recorded, but also the feeding damage caused by insect herbivores on the
 leaves and stems of the study plants. We established 18 plant species in
 ten independent study plots in the city of Darmstadt, Germany. The plants
 were six native wild plant species, six ornamental plant species related
 to the wild plants from the same genus or family, and six exotic
 ornamental plant species from other genera and families than the wild
 plants. Native insects (wild bees, flies, beetles, wasps) that feed on
 pollen and nectar visited wild perennials significantly more often (67% of
 all visits) than related ornamental (24%) and unrelated exotic plants
 (9%). In contrast, honey bees (Apis mellifera) showed no preference for
 any of the three target plant groups and interacted with other plant
 species than most other insects. The assessment of leaf damage caused by
 insect herbivores on the individual plants confirmed a similar and
 significant difference in the insects’ choices. Leaves from wild plants
 showed the highest herbivory (mean 2.3% of the leaf area), followed by
 related ornamental plants (0.8%), whereas unrelated exotic plants were
 hardly consumed (0.1%) by herbivores. Our study shows that in urban green
 spaces, both flower-visiting and leaf-feeding insects are more likely to
 use native wild plants as a food source than closely related and exotic
 ornamental plants.
description: Flower visits: Data were collected between 29
 May and 19 September 2021 at the time of peak flowering of each plant
 species. All flower visitors were surveyed once during a continuous
 10-minute survey period per plant species and plot between 9:15 am and
 5:00 pm (1550 minutes in total). Insect individuals that could not be
 clearly identified in the field were collected and later identified in the
 laboratory. Identification was based on the specific literature for each
 insect order or family. For example, wild bees were identified using the
 identification tables of Scheuchl. It was not always possible to identify
 the species precisely so the taxa designated as species also contained
 individuals that could only be identified at the family or genus level.
 These flower visitors were then designated as morphospecies, for
 example, <em>Andrena</em> 1 and <em>Andrena</em>
 2. Feeding damage: In addition to
 recording the flower visitors, the feeding damage was determined on those
 plants that were suitable for automatic damage measurement. The two
 <em>Achillea</em> species, whose leaves are pinnate, as well
 as the two <em>Campanula</em> species and <em>L.
 corniculatus</em>, whose very small leaves were not suitable for
 software-assisted evaluation, were excluded. For the other plant species,
 namely <em>C. dealbata, C. jacea, K. macedonica, K. arvensis, S.
 verticillata, S. pratensis, A. tuberosa, K. uvaria, A. x cultorum, G.
 lindheimeri </em>and <em>C.</em>
 <em>plumbaginoides</em>, five leaves per target plant species
 were taken blindly and randomly from different plant individuals in
 three-dimensional space. The leaves were photographed
 directly on-site in a picture frame with anti-reflective glass using a
 Canon EOS 40D camera. The percentage of leaf damage was then evaluated in
 the laboratory using "BioLeaf", a mobile application for
 measuring leaf damage caused by insects. In the case of leaves whose leaf
 contours had been lost due to insect damage, auxiliary lines were drawn
 before the analysis in order to reconstruct the original leaf
 shape.
description: # Home sweet home: Evaluation of native versus exotic plants as resources
 for insects in urban green spaces
 [https://doi.org/10.5061/dryad.2ngf1vhz5](https://doi.org/10.5061/dryad.2ngf1vhz5) ## Description of the data and file structure ### Files and variables #### File: data\_Home\_sweet\_home.xlsx **Description:** missing values (blank cells) Specification of the feeding damage in % of the total leaf area Plant species / plot-leaf = for example 1-3 means the third leaf of Cen_dea in the plot on **TABLE 1** Overview of plants used in the study | **Botanical name** | **Short name** | **Family** | | :----------------------------------------- | :------------- | :------------- | | **Wild plants = NATIVE** | | | | *Achillea millefolium* | Ach\_mil | Asteraceae | | *Campanula rotundifolia* | Cam\_rot | Campanulaceae | | *Centaurea jacea* | Cen\_jac | Asteraceae | | *Knautia arvensis* | Kann\_arv | Dipsacaceae | | *Salvia pratensis* | Sal\_pra | Lamiaceae | | *Lotus corniculatus* | Lot\_cor | Fabaceae | | **Ornamental plants = RELATED** | | | | \*Achillea clypeolata \*'Moonshine' | Ach\_cly | Asteraceae | | \*Campanula portenschlagiana \*'Birch' | Cam\_por | Campanulaceae | | *Centaurea dealbata* | Cen\_dea | Asteraceae | | \*Knautia macedonica \*'Mars Midget' | Kann\_mac | Dipsacaceae | | \*Salvia verticillata \*'Purple Rain' | Sal\_ver | Lamiaceae | | *Thermopsis chinensis* | The\_chi | Fabaceae | | **Exotic plants = EXOTIC** | | | | *Asclepias tuberosa* | Asc\_tub | Asclepiadaceae | | \*Kniphofia uvaria \*'Grandiflora' | Kni\_uva | Asphodelaceae | | \*Agastache x cultorum \*'Blue Boa®' | Aga\_cul | Lamiaceae | | \*Gaura lindheimeri \*'Whirling Butterfly' | Gau\_lin | Onagraceae | | \*Helenium x cultorum \*'Rubinzwerg' | Hel\_cul | Asteraceae | | *Ceratostigma plumbaginoides* | Cer\_plu | Plumbaginaceae | ## Code/software Microsoft Office Excel 2007