The Department of Environmental Affairs defines invasive alien plants as plant species that are exotic, non-indigenous or non-native to an ecosystem. These categories of IAP’s need to be controlled or removed from areas where they may cause harm to the environment or where they are prohibited.

Alien vegetation refers to plants that are not native in a country and have been brought into a country from another. The Department of Environmental Affairs in South Africa describes invading alien plants as the biggest threat to plant and animal biodiversity.

An “invasive species” is defined as a species that is. Non-native (or alien) to the ecosystem under consideration; and, Whose introduction causes or is likely to cause economic or environmental harm or harm to human health.

The present study focuses on 173 species of invasive alien plants in India. These include the most serious invasives, such as Alternanthera philoxeroides, Cassia uniflora, Chromolaena odorata, Eichhornia crassipes, Lantana camara, Parthenium hysterophorus, Prosopis juliflora and others.

Alien or naturalized species are those species which are not native to an area but established, and those that are a threat to native species and biodiversity are often called invasive species. The definition of “native” is also sometimes controversial.

Invasive species are harmful to our natural resources (fish, wildlife, plants and overall ecosystem health) because they disrupt natural communities and ecological processes. Even if the native species are not completely eliminated, the ecosystem often becomes much less diverse.

Habitat loss and invasive plants are the leading cause of native biodiversity loss. Invasive plant species spread quickly and can displace native plants, prevent native plant growth, and create monocultures.

The negative effects of invasive alien species on biodiversity can be intensified by climate change, habitat destruction and pollution. Isolated ecosystems such as islands are particularly affected. Loss of biodiversity will have major consequences on human well-being.

Invasive species can negatively impact human health by infecting humans with new diseases, serving as vectors for existing diseases, or causing wounds through bites, stings, allergens, or other toxins (Mazza et al. 2013).

Invasive species are capable of causing extinctions of native plants and animals, reducing biodiversity, competing with native organisms for limited resources, and altering habitats. This can result in huge economic impacts and fundamental disruptions of coastal and Great Lakes ecosystems.

The birds that eat the fruit of invasive plants benefit from having an abundant food source in the fall and winter, which increases their survival. Invasive plants can also serve as a source of pollen and nectar for a variety of insect species.

In fact, the study, published by the journal Nature, finds that for much of human history on the continent, human populations grew like an invasive species, which are regulated by their environment as they spread into new places. Populations grew exponentially when people first colonized South America.

One of those success stories is the eradication of the European grapevine moth (Lobesia botrana) in Northern California after it was found there in 2009.

California actually eradicated nutria in the 1970s, only to discover them again in the state’s San Joaquin Valley in 2017. Since then, California has relaunched efforts to eliminate these rodents, which can be prolific breeders.

There are three main methods used for control of invasive species — biological, mechanical, and chemical.

1. Biological control is the intentional manipulation of natural enemies by humans for the purpose of controlling pests.
2. Mechanical control includes mowing, hoeing, cultivation, and hand pulling.

10 Ways You Can Prevent the Spread of Invasive Species

• Clean your hiking and fishing gear.
• Don’t move firewood.
• Fish using native bait when possible.
• Volunteer at removal efforts.
• Talk to your local nursery when selecting plants for your garden.
• Clean your boat before transferring to a new body of water.

Volunteer at your local park, refuge or other wildlife area to help remove invasive species. Help educate others about the threat. You can even volunteer with The Nature Conservancy.

“If a large invasive tree is present that a homeowner wants to remove, I would recommend it be removed by an ISA-certified arborist prior to any type of herbicide treatment,” he says. “If the plant is small, it can be cut safely by a homeowner.”

Cleaning up ballast water is the most effective way to prevent new invasive species in the Great Lakes. The U.S. Environmental Protection Agency and the U.S. Coast Guard teamed up in 2013 to develop new rules for cleaning up ship ballast tanks.