Herb up to 3 m, with fleshy leaves in a basal rosette, spiny on the margins; similar to a cactus.
Scientific name: Eryngium pandanifolium Cham. & Schlecht.
Common name: giant sea holly
Family: Apiaceae (Umbelliferae)
Status in Portugal: invasive species (listed in the annex I of Decreto-Lei n° 565/99, of 21 December)
Risk Assessment score: (in development)
Last update: 11/07/2014
How to recognise it
Perennial herb with erect stems up to 3m.
Flowers: greenish-white becoming purplish on the fruit, arranged in capitula of 5-15 mm, ovoid–globular; capitula arranged in a dichasium, which in turn is arranged in panicles; capitula wrapped by 6-8 bracts, lanceolate–ovate, acute, entire, smaller than the capitula.
Flowering: July to August.
At a first glance, it may be confused with a species of cactus due to the marginal thorns on the leaves, yet its flowering parts are remarkably very different.
Characteristics that aid invasion
It propagates vegetatively, sprouting vigorously after being cut.
Species with a very limited distribution, being referred as causing problems just in Baixo Mondego.
Native distribution area
Subtropical area of South America.
Distribution in Portugal
Mainland Portugal (Beira Litoral).
For ornamental reasons, probably in the Coimbra Botanical Garden.
Preferential invasion environments
Very common on the slopes of Baixo Mondego, in small lakes, ditches and rice fields.
Impacts on ecossystems
It forms continuous dense populations that inhibit the growth of other species.
Reduced productivity in rice fields. Limitation of the agricultural use of the channels.
High costs in the application of control methodologies.
Natura 2000 Network habitats more subject to impacts
– Salix alba and Populus alba galleries (92A0).
Controlling an invasive species demands a well-planned management, which includes the determination of the invaded area, identifying the causes of invasion, assessing the impacts, defining the intervention priorities, selecting the adequate control methodologies and their application. Afterwards it is fundamental to monitor the efficiency of the methodologies and recuperation of the intervened area as to perform, whenever necessary, the follow-up control.
Although bibliographic references don’t reference the specific methodologies to control Eryngium pandanifolium, we suggest the use of methodologies applicable to other species that inhabit the same type of habitat and that have similar characteristics:
Hand pulling: preferential methodology for seedlings and young plants. It should be done before fruit maturation. It should be guaranteed that no larger roots and/or fragments remain in the soil.
Foliar application of herbicide. Spray with herbicide (active principle: glyphosate) limiting the exposure to the target species.
Visit the webpage How to Control for additional and more detailed information about the correct application of these methodologies.
Marchante E, Freitas H, Marchante H (2008) Guia prático para a identificação de plantas invasoras de Portugal Continental. Imprensa da Universidade de Coimbra, Coimbra, 183pp.
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