What is an Invasive and Why Should I Care?
Care and management of our Open Space parks involves more than trail-building and excellent “comfort stations”. Resource management is a big part of what goes on behind the scenes. As conscientious visitors, you might be curious when you see some plant that may or may not look out of place, and wonder whether or not it’s native to the area.
Many of the plants we see in the parks, along roadsides, in our own gardens especially, are not native to North America or the Mountain West. They are invasive. Invasives in the plant world, more familiarly called “noxious weeds” by the Colorado Department of Agriculture (CDA), are species that did not evolve here. Rather, they were transported, either accidentally or intentionally, from other parts of the globe.
Where they are native, where they evolved, they have natural enemies. Here, their enemies are absent, and, for the species that acclimate to our western environment, they not only survive, but they thrive. Think “Japanese beetle” – an insect that emigrated to the U.S. by boat around 1912 and has found a home here. Without controls, without predators, the Japanese beetle can obliterate entire gardens in a few days.
Cheat grass is an example of an invasive that was intentionally brought into the US in the mid-to-late 1800s, in the ballast of ships. It was used for packing and bedding on railroads. It spread rapidly across the country, displacing native grasses. Its impact is two-fold; it has disrupted the wildfire cycle, leading to earlier and more frequent, intense fires, and, with its lower protein content, it has made for poorer grazing on our rangelands.
In thriving without natural conditions that limit their population, invasives take over native ecosystems that have developed over millennia. Invasives have the capability to disrupt the lifecycles of the animals and insects that evolved within the native ecosystem.
In 1990, the Colorado Noxious Weed Act (CRS 35-5.5) was passed (updated in 2003). This law requires all public and private landowners in the state to maintain control over certain noxious weeds. That same year, the CDA published its first listing of flora invasives, “Noxious Weeds of Colorado”. For more information on noxious weeds go to https://ag.colorado.gov/conservation/noxious-weeds/publications
As conscientious Coloradans, it’s our duty to control invasive species. Invasive plants are divided into three lists, A, B and C. Depending on which list a plant falls under, actions are elimination (List A) and control spread (Lists B and C). So, if you find an invasive in your gardens or in our Open Space parks, control is the order of the day.
You can report invasive plant species and noxious weeds in Jeffco Open Space Parks by contacting Jefferson County Invasive Species Management, 303-271-5989. They’re located at 700 Jefferson County Parkway, Suite 100, Golden, CO 8040, with office hours Monday – Thursday, 6:30 a.m. – 5:00 p.m.
The Invasive Species team handles noxious weed and invasive plant inquiries for unincorporated Jefferson County and county open space lands.
The Jeffco Natural Resources team uses science-based methods—including hand-removal, mowing, targeted herbicide use, and biological controls—to manage invasive species across park properties.
Miss Mountain Manners encourages you to enjoy the beauty of the plant and its flowers, but if they’re invasives, don’t let them spread!
Sources:
https://ag.colorado.gov/conservation/noxious-weeds/education-and-outreach-materials
https://www.jeffco.us/795/Invasive-Species-Management
https://smallgrains.wsu.edu/bindweed/
