Boro shialmuti or Siam weed, Chromolaena odorata

Boro shialmuti or Siam weed (Chromolaena odorata, family: Asteraceae) is a fast growing perennial herb with many branches. In suitable condition, it can grow up to 10 m. Branches are hairy and glandular, stem woody. It grows in fallow land, in jungle and on the side of roads. It is regarded as an invasive plant round the globe. It has been said that, in Bangladesh, it escaped from the botanical gardens of Dhaka in the 19th centuary. It is originated in Americas, from USA to South America. 

Leaves are green, triangular-ovate, 3-10 cm long, 2-5 cm wide, deeply dented with pointed end, opposite. The leaves give off a pungent scent when crushed.

Bunch of flowers bloom in the shape of head. Flowers are small and light violet.  

Fruits are round. Seeds are achenes, hairy. Propagation of the plant is caused by seeds. The seeds usually float in the air and travel long distances. However, it can go to different places through the body of  animals and human.

Its leaves and flowers are used in the treatment of influenza, cough, fever, diabetes and bronchitis. Homoepathic medicines to cure pain and dengue fever have been prepared from it.