Insect infestation in grazing animals is an increasing problem due to factors such as global warming and increasing resistance to insecticides, which has a direct impact on animal health and welfare. According to reports from farmers, observations in zoopharmacognosy and the ingredients of commercial insecticides, various indigenous trees and shrubs with an insecticidal or repellent effect grow or can be planted on pastures.

The aim of our systematic review (designed according to the PRISMA statement) was to identify perennial woody plants from Switzerland and the wider Alpine region with a potential to affect the most common dipteran insects that are relevant for grazing animals. First, we selected 399 plant species (woody and perennial shrubs, bushes and trees) that are native or cultivable in Switzerland according to the sources Infoflora (https://www.infoflora.ch) and Flora Helvetica App (https://www.flora-helvetica.ch). Then, we created a search term which consisted of the Latin name and the English name of these plant species combined with the search term for relevant insects: ("symbovine flies" OR tabanid* OR tabanus OR musc* OR stomox* OR blowfl* OR calliphor* OR haematobia OR simuliid* OR nematocera OR gnat* OR mosquito* OR fly OR midge) NOT muscle*). Scientific information was searched in PubMed (“PubMed.Gov,” n.d.) and Web of Science (WebOfScience 2020).

Only peer-reviewed publications with an abstract in English or in one of the Swiss national languages (German, French, Italian) were considered for further evaluation. Publications were included if they described effects (regardless of the type: positive or negative) of selected plants on insect species from the search term and if the full text was available. A total of 114 publications describing 503 experiments were included in the review.