Koster's curse invades natural forests!
We know what a 'curse' means - a wish that harms or hurts another.
Then what about 'Koster's Curse'. It a curse befel our rich fauna and
also fertile soil structure, then it is simply a 'botanical curse'.
Being an invasive plant known among locals as 'Katakalu Bovitiya,
'Boo Bovitiya' and 'Kaka Bovitiya', Koster's Curse with the scientific
name Clidemia hirta and belonging to Melastomaceae family has now fast
spread in the country's wet zone and has become a severe threat to
indigenous plant species."Boo Bovitiya is one of the world's worst alien
invasive plant and it is among the world's ten dangerous plants.
What is Koster's curse
Between 1880 and 1886 a man
by the name of Koster was working to establish a coffee
plantation in Fiji, when he accidentally introduced some of
the seeds of Clidemia hirta in his coffee stock. By about
1920 islanders realised the widespread problems of this
plant, particularly in coconut groves, and called it the
'curse'. Later Koster's name was attached to it and it was
called Koster's Curse. Since its early introduction to Fiji
it has spread to many other tropical islands and caused
major problems as an invasive species.
This plant needs to be removed immediately from the environs as it
has already become a threat to our plants", Sajeewa Chamikara of the
Environment Conservation Trust (ECT)said.This a coarse perennial shrub
growing up to six feet tall with stems covered with red bristles. It
generally grows from 1 to 3 feet in height. The unique features of this
invasive plant is that its leaves which are slightly hairy with five
major veins originating at the base of the leaf and extending all the
way to its tip. Boo Bovitiya flowers with five petals are small and
It produces small bluish-black berries.Boo- Bovitiya, an invasive
shrub, believed to be a native to South America, was introduced as an
ornamental plant to Sri Lanka and naturalised in several tropical
countries. It is widely distributed along rain forest pathways and
streams of wet and montane zones. Also in roadsides and disturbed
grounds of lowland wet zone to tea estates in the upcountry. Propagation
is mainly due to seeds spread by birds - Yellow - browed Bulbul, White -
browed Bulbul, Black - capped Bulbul, Yellow - eared Bulbul, Legge's
Flowerpecker and Small Flower pecker.
The shrub has become common in wet open or disturbed places with
abundant moisture. Boo Bovitiya can grow vegetatively and reproduce
throughout the year."Its success as an invasive species is due to
prolific seed production, high seed viability, rapid growth, broad
environmental tolerances, and abundance of dispersal vectors including
birds, pigs, and humans.
The shrub spreads rapidly into forest gaps that have been opened due
to disturbance. Once it becomes established Koster's curse forms dense
monotypic stands that shade out all the understory vegetation", he said
adding it can suck out the nutrients from the soil very fast, making it
difficult for other plants to live.Koster's Curse originated in Central
and South America and later spread to Mexico to Paraguay and
unfortunately the plant started spreading in Fiji, Australia, South East
Asia and Hawaii.
The plant became a curse to the fragile ecosystems of Hawaii, where
it was first recorded from the island of Oahu in 1940 and by mid 1970s
it spread in over 90,000 hectars. Now it is found on all major Hawaiian
islands.Explaining the impact of Boo Bovitiya, Sajeewa said the plant
has the ability of spreading rapidly disturbing without any natural
predators. According to ECT findings Boo Bovitiya has become a threat in
10 districts - Colombo, Gampaha. Kegalle, Ratnapura, Galle, Matara,
Kandy, Nuwara Eliya and Matale. "Boo Bovitiya has raidly spread in the
environs of the Sinharaja forest and also Sri Pada. Swathes of this
plant can be seen in almost all the forests in the wet zone.
It grows like a bush, blocking sunlight for other plants below it",
he said adding that the rapid growth of this plant has affected plants
growing underneath."Its spread threatens indigenous plants that grow in
the same areas. There are also fears that the rapid spread of the shrub
could harm the ecological balance as well as threaten wild life like
elephants", he said.The environmentalists said the responsibility of
destroying and controlling spreading of Boo Bovitiya is on the hand of
the Forest Department and the Department of Wildlife Conversation
(DWLC). Sajweewa said destroying Boo Bovitiya was easy as bushes around
one plant would be easily uprooted and need no machinery to uproot the
plants. "As it prop up from the roots, the best way is to uproot the
entire plant without leaving roots.
The uprooted plants need to be burnt to prevent them re-growing", he
said.The environmentalists said lack of knowledge how this worst
invasive shrub make a huge impact on local ecosystem was one reason to
its rapid spread. They pointed out one effective measure to eliminate
Boo Bovitiya was to educate people, especially the villagers and
children on the harm that this plant cause to our own plants and soil.
Pix courtesy - Environment Conservation Trust