News Highlights:
Exotic invasive plant Senna spectabilis: The Nodal Centre for Biological Invasions (NCBI) at the Kerala Forest Research Institute (KFRI) has come out with a management plan to eradicate Senna spectabilis, the exotic invasive plant that is posing a severe threat to the State’s wildlife habitat.
Key Takeaway:
- Due to the mass flowering and drying of bamboo species in Wayanad, many open spaces (78.91 sq km) have been occupied by Senna spectabilis.
- The plant has also started to invade the adjacent Bandipur and Nagarhole tiger reserves in Karnataka and Mudumalai tiger reserve in Tamil Nadu.
Senna spectabilis
- About
- Senna spectabilis is a plant species of the legume family native to South and Central America.
- They are often grown as ornamental in front yards, parks, gardens, buildings, etc., due to their bright yellow flowers that bloom during summer. They are also known as golden wonder trees.
- The plant has become an invasive alien species in parts of Africa such as Kenya, Malawi, Tanzania, Uganda, and South India.
- Description:
- Senna spectabilis is a shrub or deciduous tree that can grow anywhere from 15 to 20 ft in height and 15–20 ft in width.
- have a rounded vase-shaped crown, which is dense and symmetrical.
- S. spectabilis is pollinated by bees and has a high-speed growth rate.
- Foliage:
- A rounded, evergreen foliage arranged alternatively.
- The leaf type is an odd-pinnately compound with pinnate leaf venation and 4–15 pairs of leaflets, each growing to as large as 7.5 cm.
- The leaves are green and yellow and remain so year around.
- Flower and fruit:
- Bright yellow inflorescence 10–50 cm long, containing a 3.5–4 cm in diameter corolla with five unequal petals.
- The flowers are very showy, producing elongated pod-shaped fruits about 6–12 inches in length.
- Distribution:
- Senna spectabilis is native to South America, first found in eastern tropical Brazil and coastal Ecuador, eventually migrating throughout Central America and the West Indies in forests from up to 2000 m of altitude.
- Their habitats include rainforests, semi-deciduous and dry forests, montane forests, and dry valleys.
- Uses:
- Senna spectabilis has a few medicinal properties.
- The plant can be used as a treatment for ringworm and skin diseases.
- After extracting a leaf from alcohol, there was significant antifungal activity, which suggests it can be used for infections caused by Candida albicans.
- IUCN Red List:
- It is categorised as ‘Least Concern’ under IUCN Red List.
Invasive Alien Species:
- About:
- An alien species is a species introduced outside its natural past or present distribution; if this species becomes problematic, it is termed an invasive alien species (IAS).
- The Convention on Biological Diversity (CBD) defines IAS as “an alien species whose introduction and spread threaten ecosystems, habitats, or species with socio-cultural, economic and environmental harm and harm to human health.
- Threats:
- direct impact on human health. They have potential threats to livestock health.
- Biological invasions significantly threaten global food security and livelihoods, with developing countries being the most susceptible.
- The biological invasion could lead to changes to fire regimes, disease transmission to native species, forest loss, reduction in water flows, and habitat transformation, among others.
- Invasive alien species reduce the resilience of natural habitats, making them more vulnerable to the impacts of climate change.
- They are the most common threat to amphibians, reptiles and mammals on The IUCN Red List.
- On average, 32% of the farmers’ budget goes into the control of weeds, which includes the regular spraying of insecticide and labour costs.
- Significance:
- Some of the species are not weeds but are highly economic species.
- Though they are a weed, they are of high medicinal value, being a potent source of Vitamin D-3.
- Such weed could be a potential crop for the people living in the vicinity of the park to uplift their livelihood.
- Conservation and propagation of the members of the Poaceae family in a very holistic manner will help counter the shrinking grasslands.
Pic Courtesy: Freepik
Content Source: The Hindu