Parthenium

Starr 050423-6650 Parthenium hysterophorus

Parthenium IMG20200104105005

Parthenium infestation in Achanakmar Wildlife Sanctuary

Parthenium is a genus of flowering plants in the Asteraceae family. The genus is native to the Americas, but several species have become invasive in other parts of the world. The most well-known species is Parthenium hysterophorus, commonly known as Santa Maria feverfew or whitetop weed.

Description

Parthenium species are typically annual or perennial herbs or shrubs. They have deeply lobed leaves and produce small, white, daisy-like flowers. The plants can grow up to 1.5 meters in height. The flowers are arranged in clusters, and each flower head contains both disk florets and ray florets.

Distribution

The genus Parthenium is originally from the Americas, particularly in regions ranging from the southern United States to South America. However, species like Parthenium hysterophorus have spread to other continents, including Asia, Africa, and Australia, where they are considered invasive.

Ecological Impact

Parthenium species, especially Parthenium hysterophorus, are known for their aggressive growth and ability to outcompete native vegetation. This can lead to a reduction in biodiversity and negatively impact agricultural productivity. The plant releases allelopathic chemicals that inhibit the growth of other plants.

Health Implications

Contact with Parthenium plants can cause allergic reactions in humans, including dermatitis and respiratory issues. The pollen is a known allergen and can cause hay fever and asthma in sensitive individuals.

Control Measures

Managing the spread of Parthenium species involves a combination of mechanical, chemical, and biological control methods. Mechanical control includes regular mowing and hand-pulling, while chemical control involves the use of herbicides. Biological control has been explored using natural enemies like the Zygogramma bicolorata beetle.

Species

Some notable species within the Parthenium genus include:

• Parthenium argentatum - commonly known as guayule
• Parthenium hysterophorus - commonly known as Santa Maria feverfew
• Parthenium integrifolium - commonly known as wild quinine

Related Pages

• Asteraceae
• Invasive species
• Allergic reactions
• Biological control