What is an Invasive Species?


An invasive species is a non-native organism (plant, animal or disease) that can or does harm a new environment. Invasive species can be a relocated native species that does harm in its new home or an invasive species can be a foreign species from another continent.


MOST invasive species are moved by humans! How do I know it is an invasive species?

Drought Tolerant Plant Choices and What to Avoid

Report a Pest iPhone App

Have you seen a new or unusual plant or pest in your area? If so, this app is perfect for you!

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How Can You Help?

Forestino says, "You can play an important role in protecting your state's agriculture and your environment by reporting the sighting of a pest that you suspect may be a new invasive species in your area."

Go to Report a Pest Page

CA Invasive Species List

Purple Loosestrife (Image Citation:(?) Doug Landis, Michigan State University, Bugwood.org)

The California Invasive Species Advisory Committee has created a list of invasive species that threaten California. This list includes species of all taxonomic types — vertebrate, invertebrate, plant and disease.

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Bringing plants & animals into CA?

Invasive Species

The natural beauty of water-hyacinth's flower and foliage has helped it spread to become a floating nightmare in many tropical areas. (Image Citation:(?) Willey Durden, USDA Agricultural Research Service, Bugwood.org)

So just what is an invasive species? An unofficial definition could be that an invasive species is a species that does not naturally occur in a specific area and whose introduction does or is likely to cause economic or environmental harm or harm to human health.

Go to Invasive Species Page

Native Species

Sebastopol meadowform (Limnanthes vinculans ) - Photo: Wikimedia

A Native Species is found in an area, has developed in that area, and is usually kept in control by other native species of the area. Native species can be harmless, beneficial or a plant/animal/insect pest, in their area of origin.

Go to Native Species Page

Endangered Species

Beneficial species are those organisms that are good for the environment. In insect species, these keep other insects in balance with the environment. Some beneficial insects are native and some are specifically imported foreign species to fight an insect problem.

Go to Endangered Species Page