page banner blank
Banner for name withlogo
 

INVASIVE ALIEN SPECIES


FLORA

For a small island, Sri Lanka is rich in biological diversity. Yet, this natural wealth is under threat from various sources, including invasive alien species. IAS grow rapidly, compete vigorously, push out native species and alter ecosystems. Their impacts are enormous and they have the potential to cause damage to the environment, human health, livelihoods and the economy.
 
 
 
 

Shrubby dillenia

(Dillenia suffruticosa)

 Family: Dilleniaceae

Common names: Shrubby dillenia (English); Para (Sinhala)

Synonyms: Dillenia burbidgei; Dillenia suffruticosa var. borneensis; Wormia suffruticosaShrubby dillenia

Taxonomic notes: N/A

Character Identification: Dillenia suffruticosa is a large evergreen shrub with sprawling branches. The leaves are spirally arranged and are elliptic to obovate in shape. They are large and measure 12-37 cm in length and 6-25 cm in width. The leaves bear a 1-5 cm stalk that is broadly winged. Flowers are yellow, scentless and large and measure 10-13 cm in width. The flowers are found on long stalks, facing downwards. Fruits are tightly covered by fleshy sepals that split open to display red seeds (Ashton et.at, 1997).

Total Height: 7-10 m

Morphologically similar species: This species is very similar to the two endemic species Dillenia retusa and Dillenia triquetra, however, D. suffruticosa can be distinguished by the winged-petiole and yellow colour flower, whereas the endemic species bear white colour flowers.

History and introduction: The Shrubby dillenia was introduced to Sri Lanka as an ornamental plant from Borneo in 1882, by the Royal Botanical Gardens (Wijesundara, 2008).

Present Distribution:

Dillenia suffruticosa is a native of Southeast Asia and is known to be from the Malay Peninsula, Singapore, Sumatra and Borneo. It is the national flower of Brunei. The plant has been introduced to Panama, Costa Rica, the Philippines, Nicaragua, Jamaica, Seychelles, Myanmar Thailand and Hawaii (USA) (Hassler, 2014).

In Sri Lanka, D. suffruticosa has established itself in the low country wet zone, noticeably in the Kalutara, Galle and Rathnapura districts. They are generally found in marshy areas, forest edges, open scrublands and roadsides (Wijesundara, 2008). This species is commonly seen in Kanneliya Forest Reserve.

Dispersal and reproduction (pollination and dispersal): Seeds of D. suffruticosa are dispersed by birds that feed on the fruits of this tree.

Impact on native species and habitats:

Dillenia suffruticosa is reported to structurally alter soil and thus affect the mobility of soil nutrients. This in turn affects the nutrient uptake of any native plant species that grows underneath D. suffruticosa (Wickramathilake et. at, 2014). Furthermore, D. suffruticosa is reported to suppress the growth of native plants and establishment of seedlings growing beneath it by physically shading the ground (Wickramathilake et al., 2014).

Direct exploitation/ destruction of native species:

Direct exploitation of native species has not been reported for this species.

Current Uses: Dillenia suffruticosa is cultivated as an ornamental plant. Extracts from leaves and roots are known to have medicinal properties (Armania et al., 2013). It is also used by farmers to cover the seadlings of other crop species.

Natural threats (pest/predators): None reported.

Prevention and Control: Not known

123456drowingfieldmap

 
 
IAS Documentary
Information for the public knowledge about Invasive Alien Species in Sri Lanka...

AS policy Intro
Information about the policies of Invasive Alien Species in Sri Lanka...



Join with us








Contact us

“Sobadam Piyasa”
416/C/1, Robert Gunawardena Mawatha
Battaramulla
Sri Lanka

Tel:   009411  2034100
Fax:  009411  2879972
Email: ias.biodiversity@yahoo.com

© Copyright 2016 Biodiversity Secretariat. All rights reserved