On their home turf, plant and animal populations are kept in check by natural controls, like predators and food supply. However, when a species is introduced, accidentally or intentionally, into a new landscape- one not adapted to its presence-the consequences can be devastating. "Invasive" plants and animals sometimes spread unchecked, disrupting natural cycles, crowding out native species and costing billions in property damage and lost economic productivity.

Did You Know?

• More than 4,500 foreign species have gained a permanent foothold or taken root in the U.S. during the past century.


• Invasive species contribute to the decline of 46% of the imperiled or endangered species in the U.S.


• Invasive species cost an estimated $137 billion in annual losses to agriculture, forestry, fisheries and the maintenance of open waterways in the U.S.

In Oklahoma, biodiversity threats from invasive plants like Sericea lespedeza and eastern redcedar severely impact open rangelands and forests, while stream banks and sandy floodplains are being invaded by salt cedars. These three plant species are damaging more wildlife habitat and productive landscapes in Oklahoma than any other plant species.

Sericea lespedeza (upper right) is an aggressive non-native legume introduced decades ago for livestock forage. It is now spreading from the Atlantic Coast and Florida to Texas, Oklahoma and as far north as Michigan. This plant is displacing native vegetation, altering habitat and increasing land management costs. Control options include spraying expensive herbicides and possibly controlled burns.

Eastern redcedar is actually native to Oklahoma, but with the absence of fire on the landscape this juniper is estimated to be spreading at the rate of 720 acres per day in our state- creating relatively sterile cedar forests and increasing soil erosion underneath its canopy. Control options include controlled burning and mechanical removal.

Salt cedar is s small tree or shrub approximately 20 feet in height. Native to Asia and eastern Europe, this invasive plant now occupies many of our stream banks and floodplains. Left unchecked it will grow into a dense thicket, consuming huge volumes of water. Control requires a combination of spraying special herbicide, burning and mechanical removal for long term effectiveness.

What the Conservancy is doing now combats these invasives with a combination of prevention, eradication, restoration, research and outreach. The Conservancy is also advocating public policy measures to help win the battle of invasives in Oklahoma.