Denver's Invasive Plant Rules: The Rules That Matter

Every city handles invasive plant rules a little differently. In Denver, Colorado, there are 4 distinct rules that residents and property owners should be aware of. Some are stricter than what neighboring cities enforce, and others are more relaxed. Here is what you need to know.

Tree-of-Heaven Removal

Colorado Department of Agriculture lists Ailanthus altissima (tree of heaven) as a List B noxious weed under the Colorado Noxious Weed Act. Denver Forestry requires removal on private property and bans planting under DRMC chapter 57 right-of-way standards.

Key details: State list: Colorado List B. Authority: C.R.S. 35-5.5. Lead agency: Denver City Forester. Lanternfly host: Yes major.

Failing to control Ailanthus after a Denver Forestry notice violates DRMC chapter 57 with fines up to $999 per day, city abatement at owner expense plus a lien. Lanternfly host violations may bring state quarantine.

Bamboo Restrictions

Denver does not have a specific ordinance banning or restricting bamboo. Colorado's Noxious Weed Act does not list bamboo as a noxious weed. Running bamboo that spreads to neighboring properties may be addressed as a nuisance under general city code.

Key details: Bamboo Ban: No citywide ban. State Noxious Weed: Bamboo not listed in Colorado. Climate Factor: Semi-arid limits spread. Best Practice: HDPE barrier 24-30 inches deep.

No direct penalty for planting bamboo. Nuisance complaints may result in enforcement action if bamboo encroaches on neighboring property.

Denver is more permissive than most cities when it comes to bamboo restrictions. That said, there are still limits.

Prohibited Species

Denver enforces the Colorado Noxious Weed Act, which classifies invasive species into List A (eradication required), List B (management required), and List C (advisory). Common prohibited species include Russian olive, musk thistle, and diffuse knapweed.

Key details: List A: Must eradicate (African rue, giant salvinia). List B: Must manage (Russian olive, musk thistle). List C: Advisory (common mullein). Authority: CRS 35-5.5 Colorado Noxious Weed Act.

Failure to manage List A weeds: enforcement action by Colorado Dept. of Agriculture. Fines up to $100/day under state law.

Front Yard Gardens

Denver allows front yard food gardens and edible landscaping. Colorado law (HB19-1050) prohibits HOAs and municipalities from banning vegetable gardens. The city encourages water-wise landscaping and allows xeriscaping in front yards.

Key details: Front Yard Gardens: Permitted by state law (HB19-1050). HOA Bans: Prohibited by Colorado law. Xeriscaping: Encouraged by city. Rainwater Collection: Two 55-gallon barrels allowed.

No penalty for front yard gardens. Weed violations: fines if vegetation exceeds 6 inches in unmaintained areas.

If you are coming from a city with tighter rules, you will find Denver gives residents more flexibility on front yard gardens.

The Bottom Line

Compared to many U.S. cities, Denver gives residents more room on invasive plant rules. 2 of the 4 rules here are rated permissive. But permissive does not mean unregulated. There are still requirements, and the city does enforce them when violations are reported.

All of the above reflects Denver's municipal code as of our last review. If you need specifics on fines, exemptions, or filing requirements, the detailed ordinance pages linked above have the full breakdown.