Invasive Species Removal
Stewarding our regional greenway
The Conservancy is advancing work to protect and restore the Canal’s plant community by removing invasive species that degrade the ecological health of the Canal corridor. Current programs focus on removing invasive Russian olive from the corridor in partnership with the Mile High Youth Corps.
Russian Olive Removal
Russian olives are a non-native, invasive species that spreads aggressively, displaces native vegetation and competes with desired vegetation for scarce water resources on the Canal. As Denver Water reduces its reliance on the Canal for irrigation delivery, controlling the spread of Russian olive is essential to protecting the Canal’s ecological health. The Colorado Department of Agriculture (CDA) characterizes Russian olive as a species that taxes water reserves, disrupts plant succession and interferes with nutrient cycling patterns. Russian olive is designated as a List-B noxious weed by the CDA, meaning local governments are required to manage and limit its spread. Colorado Parks and Wildlife projects that Russian olive will displace native plains cottonwoods as a climax species; this is particularly concerning as cottonwoods are the most prevalent mature tree along the Canal, composing over 40% of the canopy. As the Canal’s cottonwoods near the end of their lifespan and become increasingly stressed by competition for scarce water resources, it is crucial that we remove Russian olive from the corridor.
To address this need, the Conservancy launched a program to remove Russian olive along the Canal in partnership with the Mile High Youth Corps (MHYC). This program is one component of a holistic approach to protecting and restoring the Canal’s canopy; the complete approach includes data collection, invasive tree removal, tree canopy care and tree planting programs. In 2022, the Conservancy worked with MHYC for eight weeks, during which crews inventoried and removed 392 Russian olives across 21 miles of Canal corridor in Denver, unincorporated Arapahoe County, Centennial and Greenwood Village. In 2023, MHYC will spend four weeks inventorying and removing Russian olive on the Canal in Greenwood Village and Cherry Hills Village.
Visit our blog to learn more about the history and impacts of Russian olive on Colorado’s open spaces.
Russian Olive Removal FAQs
In 2023, the Conservancy will partner with MHYC for four weeks of work on the Canal, scheduled April 17-April 27 and November 6-17. MHYC will start along the corridor in Greenwood Village and move north into Cherry Hills Village.
You may see cut Russian olives on the trail shoulder during this project. MHYC will pile cut Russian olives on the trail shoulder as they move down the corridor. A contractor will then come to chip the material and dispose of it offsite.
If untreated, Russian olive can easily resprout from stumps and root suckers. To prevent this, MHYC will perform cut-stump treatments–applying small amounts of herbicide directly to Russian olive stumps immediately after cutting. This prevents the trees from resprouting. Additionally, after the project is complete, the Canal Conservation Corps will monitor the project area and address any regrowth. This approach will ensure sustained control of Russian olive along the corridor. Learn more about joining the CCC here!
This project is made possible through grant funding. The Conservancy has been awarded GOCO’s Conservation Service Corps grant to fund this project in 2023. Learn more about GOCO’s investment across the state to enhance trails, parks, open spaces and wildlife habitat:
The Colorado Youth Corps Association announced that 250 Colorado young people will get jobs this summer working on critical outdoor recreation and land conservation projects throughout the state. These projects will enhance Colorado’s trails, parks, open spaces, and wildlife habitat in 17 counties throughout the state. Funds for this project were awarded by Great Outdoors Colorado (GOCO), which receives a portion of Colorado Lottery proceeds, through the Colorado Youth Corps Association for use by accredited conservation service corps.
The goal of the program is to employ crews throughout the state on critical outdoor recreation and land conservation projects in partnership with local governments and open space agencies. In June 2022, the GOCO board announced that GOCO would invest $1,000,000 of funding in conservation service corps work in 2023. 
