International ragweed day (2015-06-27)
2015-06-27 is the ‘international ragweed day’ which aims to promote awareness raising on the negative impacts of Ambrosia artemisiifolia (Asteraceae) (EPPO List of Invasive Alien Plants). A. artemisiifolia is native to North America and a widespread invasive alien plant in the EPPO region. A. artemisiifolia is an annual species and a prolific seed producer - some specimens can produce up to 100 000 seeds. Seeds remain viable for 5-14 years. On heavily infested plots the population density can reach 500 plants per m2. The species invades crop fields, orchards and vineyards and is commonly found along waterways, transportation networks and wasteland. A. artemisiifolia produces a large amount of pollen that is highly allergenic and can result in severe human respiratory symptoms such as asthma. As A. artemisiifolia invades crop systems this can result in a decline in yields. The annual economic cost of this invasive alien has been estimated at c. 4.5 billion EUR for Europe alone. An EU-Cost Action (FA1203) on the sustainable management of A. artemisiifolia was initiated in 2012 and involves over 250 scientists from 33 countries with the aim of coordinating the management of this species across Europe.
International ragweed day website:
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