> Home | Planning & strategies | Horticulture
Keeping horticulture green

Missouri Botanical Garden
Missouri Botanical Garden

Plants are essential to sustaining the stability and quality of human life on Planet Earth. Their loss threatens the future of our children and our grandchildren. Today Earth has lost a third of its forests, a quarter of its topsoil, and plants and animals are disappearing faster than we can learn about them, or even know what is gone. Invasive non-native plants pose one of the most serious threats to the protection of biological diversity worldwide, and the introduction and spread of these adventive species continue, in many cases, unchecked.

In December 2001, the Missouri Botanical Garden and the Royal Botanic Gardens, Kew, were honored to convene experts from across the globe to explore and develop workable, voluntary approaches for reducing the introduction and spread of non-native invasive plants. This landmark three-day gathering, The Workshop on Linking Ecology and Horticulture to Prevent Plant Invasions, made important progress. It produced the St. Louis Declaration, which includes Findings and Principles that frame the invasive plant species problem and offer a basis for practical and effective ways to address the problem. More significantly, The St. Louis Declaration also offers Voluntary Codes of Conduct. These codes can serve as guides for responses to curb the spread of invasive plant species, while promoting courses of action that will minimize this spread.

The Threat from Invasive Plants
In the United States invasive species rank as the number one threat to biodiversity in protected areas. Natural areas managers have consistently identified invasive species in their top threats to conservation sites. If we are to be successful at protecting the world's biodiversity, and therefore our own well being, the threat from invasive species will need to be addressed.

There are many pathways for invasive species to enter natural systems. They can either be intentional as in the case of starlings being introduced to Central Park, or unintentional by hitchhiking insects, like Asian longhorn beetles coming in with shipments from other countries. For intentional introductions, it is estimated that in many regions of the U.S. the greatest percentage of invasive plants are coming from gardens and landscaping.

It is this pathway of introduction, intentional through gardens and landscaping, that the Invasive Species Team and the horticulture industry is working to minimize.

Codes of Conduct
The Missouri Botanical Garden and Royal Botanic Gardens, Kew, with participation from the horticulture industry and other professionals hosted a workshop in 2001 to develop strategies that will help reduce these new introductions. Participants from several fields including government, garden clubs, horticulture industry, and botanical gardens, developed a set of Codes appropriate for each of their respective interest groups. These Voluntary Codes of Conduct are the focus of the Preventing Invasion through Horticulture project.

(Text on this page adapted from comments by Dr. Peter Raven, Director of the Missouri Botanical Garden.)

Codes of Conduct
The Findings and Principles that were developed at the Missouri Botanical Gardens 2001 Workshop.

Using the Codes
Information on how to implement these Codes with your business, organization or other group. Examples of how to implement each of the Codes are given.

Cultivars are plant strains that have been selected for various horticultural characteristics. How do they fit into the issues of invasive species and horticultural plants?

Other resources
Tools such as brochures to help you in your work to stop invasions through horticulture.

Weed Information Management System (WIMS)
A fully-integrated hardware and software application for mapping invasives and tracking management actions.
Remote sensing
A review of remote sensing technology, as applied to invasive species detection and mapping.
Templates and examples
Adaptive management planning tools such as model plans for sites, weed control templates, etc. Very useful!
Invasive species learning networks
Learn about Invasive Species Networks that help promote best practices for invasive species abatement among staff in The Nature Conservancy, partner agencies, and other organizations.
Volunteer coordination and public outreach
Powerpoint presentations on invasive species, weed pamphlets, on developing weed management areas, and more.

Other site resources

Conservation stories
Invasive species management is not impossible. Read these success stories and be inspired.
Assessments and regional plans
Assessments of invasive species issues for various operating units in The Nature Conservancy.
Weed Control Methods Handbook
An electronic handbook provides detailed information on the use of manual and mechanical techniques, grazing, prescribed fire, biocontrol, and herbicides, to help you control undesirable invasive plants.
Join our listserve to voice your frustrations and trumpet your successes.

Updated July 2008
©The Nature Conservancy, 2005