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| Last Updated:: 23/09/2019

Unwanted Guests





Six invasive species threaten the native flora of Tirusulam hillock and if unchecked can alter its ecosystem




Lantana camara

  • An invasive shrub from Central America that came to the country in 1809 as an ornamental flower to the botanical garden in Kolkata.
  • There is no predator for this shrub and hence it proliferates across the country





  • When India imported PL480 wheat from the United States in the 1960s, the weed came with the consignment.
  • This plant has invaded plains and wooded areas, and causes respiratory and skin allergies





  • The tree was imported in the 1960s from South Africa to meet the state’s firewood demand. But it invaded water bodies across the state.
  • Though its seeds are eaten by deer and goat, they re-enter the ecosystem through their droppings




Mikania micrantha

  • A creeper brought by British troops during the Second World War to be used as camouflage, it can alter the character of the ecosystem it invades





  • Botanists say the plant came from China. It wraps around a host plant and can enter its vascular system.
  • Cuscuta can grow up to the canopy of the host and kill it.







Source: The Times of India, 23 September 2019, Chennai.