Pormenor da flor.

Datura stramonium

Annual herb or subshrub, up to 2 m, of large, white funnel-shaped flowers and spiny fruits.

Scientific name: Datura stramonium L.

Common names: jimsonweed, common thorn apple, devils trumpet, jamestown-weed, stinkwort

Family: Solanaceae

Status in Portugal: invasive species (listed in the annex I of Decreto-Lei n° 565/99, of 21 December)

Risk Assessment score: (in development)

Synonymy: Datura talula L., Datura inermis Juss. Ex Jacq., Datura stramonium L. var. tatula (L.) Torr.

Last update: 11/07/2014

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How to recognise it

Annual herb or subshrub of 50-200 cm, glabrous to puberulent.

Leaves: with 5-21 X 4-15 cm, ovate to elliptic, cuneate to subcordate on the base; sinuatedentate to –lobate.

Flowers: large (5-10 cm), funnel-shaped, white or purple.

Fruits: capsules with 2,5-7 X 2-5 cm, ovoid, erect, densely coated with spines ± equal in length, almost always spiny.

Flowering: June to October.

 

Similar species

There are other species of Datura but they have either significantly larger or smaller flowers than Datura stramonium, so they’re not to be mistaken.

 

Characteristics that aid invasion

It propagates by seed and produces seeds that have great ability to germinate at any time of the year. Each capsule may contain around 500 seeds. A plant may produce up to 30000 seeds, which may be viable for over 40 years.

 

 

Native distribution area

South Tropical America.

 

Distribution in Portugal

Mainland Portugal (all provinces).

Geographic areas where there are records of Datura stramonium

Other places where the species is invasive

Temperate, tropical to subtropical regions in North, Central and South America, Europe, Asia, Africa and New Zealand.

 

Introduction reasons

Probably accidental.

 

Preferential invasion environments

Mainly crop areas, ruderal places and other wastelands. It also invades natural and semi-natural areas.

 

Impacts on ecossystems

The seedlings establish rapidly and form great mats that shade the surrounding vegetation, thanks to their large leaves.

It has allelopathic effects that inhibiting the development of other species.

 

Economic impacts

It interferes in the production/productivity of agricultural areas.

 

Other impacts

All parts of the plant, especially the seeds, are very toxic and may be fatal if ingested by humans and other animals.

 

 

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.

The control methodologies used for Datura stramonium include:

 

Physical control

Hand pulling: preferential methodology for seedlings and young plants. It should be done before fruit maturation. In more compacted substrates, hand pulling should be done during the rainy season as to facilitate the removal of the entire root system .

 

Chemical control

Foliar application of herbicide: applied to young plants. Spray with herbicide (active substance: glyphosate, dicamba) limiting as much as possible its application to the target species.

 

Visit the webpage How to Control for additional and more detailed information about the correct application of these methodologies.

CABI (2012) Datura stramonium. In: Invasive Species Compendium. CAB International, Wallingford, UK. Available: http://www.cabi.org/isc/ [Retrieved 10/11/2012].

Dana ED, Sanz-Elorza M, Vivas S, Sobrino E (2005) Especies vegetales invasoras en Andalucía. Consejería de Medio Ambiente, Junta de Andalucía, Sevilla, 233pp.

Dufour-Dror J-M (2012) Alien invasive plants in Israel. The Middle East Nature Conservation Promotion Association, Ahva, Jerusalem, 213pp.

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.

USDA, NRCS. (2012) The PLANTS Database. National Plant Data Team, Greensboro, NC 27401-4901 USA.  Available: http://plants.usda.gov [Retrieved 10/11/2012].

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