EPPO Global Database

The following guidelines for the management of Ambrosia artemisiifolia (Asteraceae, EPPO List of Invasive Alien Plants) are based on the results of the European project “Strategies for Ambrosia control (AMBROSIA)” funded by EUPHRESCO in 2008 and 2009. Project partners were the Aarhus University (Denmark), the Agricultural Institute of Slovenia (Slovenia), Agroscope ACW (Switzerland), the Julius Kühn Institute (Germany) and the Copenhagen University (Denmark).

The guidelines present the native range and the distribution of A. artemisiifolia, information on its identification and morphological descriptions with pictures of species that could be mistaken for it, including the seedling stage. In addition to descriptions of Ambrosia maritima, Ambrosia trifida and Ambrosia coronopifolia, examples of species which have been mistaken for A. artemisiifolia in different habitats are given:

The guide also contains information on the biology and ecology of A. artemisiifolia and on its seed dispersal. The pathways of introduction identified are the following:

- Sunflower seeds.

- Birdseed mixture: in a survey in Germany, fruits of A. artemisiifolia were found in about 70% of the samples of birdseed mixture. Surveys in Switzerland and Denmark gave similar results.

- Transport by machinery/equipment: A. artemisiifolia is reported to have been introduced in the region of Geneva (CH) by combine harvesters rented in the area of Lyon (FR).

- Transport of soil/gravel: transport of soil and gravel between neighboring countries is a common practice in parts of Europe, particularly between Switzerland, France and Italy.

- Compost: compost may allow surviving seeds to be dispersed, as the seeds of A. artemisiifolia seem to be heat tolerant.

- Water courses: some seeds of A. artemisiifolia can float and be spread by water currents.

The guidelines then indicate preventive measures, control methods and strategies, as well as data on the negative impacts of this species on human health and the economy.