Invasive Allergenic Plants (IAS)
Alien invasive species spreading in the programme area and causing allergies
Why are invasive plants a problem?
Invasive alien species threaten biodiversity, disrupt ecosystems, and cause economic damage.
Ragweed
Ambrosia artemisiifolia L.
Very high allergenic potentialRagweed is one of Europe’s strongest allergenic invasive plants. Its tiny pollen grains can travel over very long distances.
Origin
North American continent
Flowering season
July - October
Spread
Very fast, especially along roads and construction sites
Recognition
- •Deeply lobed leaves
- •Hairy stem
- •Yellowish flower spikes
- •Often found on disturbed land
Control measures
- •Mechanical uprooting with roots
- •Repeated mowing before flowering
- •Herbicide use under supervision
- •Report sites to authorities
Goldenrod
Solidago canadensis L.
Medium allergenic potentialCanadian goldenrod forms dense colonies and can outcompete native species in affected habitats.
Origin
Canada and USA
Flowering season
August - October
Spread
Moderately fast via rhizomes and seeds
Recognition
- •Height 60-200 cm
- •Dense yellow flower clusters
- •Lance-shaped leaves
- •Common near rivers and woodland edges
Control measures
- •Repeated mowing several times per year
- •Rhizome removal in spring
- •Continuous monitoring of regrowth
Japanese knotweed
Reynoutria japonica Houtt.
Low allergenic potentialJapanese knotweed is among the hardest invasive plants to control and can fully displace native vegetation.
Origin
East Asia
Flowering season
Flowering: August - September
Spread
Aggressive spread through rhizomes
Recognition
- •Hollow bamboo-like stems
- •Heart-shaped leaves
- •Small white flowers in clusters
- •Frequent along rivers and roadsides
Control measures
- •Long-term multi-year control
- •Rhizome removal on small sites
- •Herbicide application under expert supervision
Report an invasive plant site
Have you noticed an invasive plant? Help us map its locations.
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