by Alan Carpenter

Invasive plant species are becoming increasingly prevalent in Colorado, particularly in riparian areas. Controlling undesirable invasive plants is a challenge to land managers across the spectrum from public to private and is a concern regardless of whether one’s goal is to provide forage for livestock or recreation amenities for people. Noxious weeds are a sub-set of invasive plants and are those species that landowners and managers must control according to state statute or local ordinance. I have found that many landowners and managers are not especially familiar with noxious weeds. Therefore, I have included several articles about invasive plants in this issue of green line to help acquaint CRA members about this major threat to riparian areas and to alert readers to several sources of useful information about noxious weeds.
This issue contains a profile of one of Colorado’s worst weeds of Colorado’s riparian areas and wetlands, namely purple loosestrife. This article is reprinted from Creating an Integrated Weed Management Plan: A Handbook for Owners and Managers of Lands with Natural Values, which was published in 1999 by the Colorado Natural Areas Program. It contains a wealth of information about noxious weeds, including profiles of all of nearly all of Colorado’s noxious weeds. You can download the text of the Handbook at http://
This issue also highlights Governor Owens’ recent Executive Order to eradicate tamarisk on state lands in Colorado. Finally, the General Assembly passed a law this session that modifies the Colorado Noxious Weed Management Act, clarifying the duties of landowners, local governmental units, and the state in managing noxious weeds. The revised act will create new lists of noxious weeds that are slated for eradication, suppression, or containment. We have included a brief synopsis of the changes to the state weed law.

Colorado Riparian Association