Why is this pesticide banned in Colorado - Ask Extension
I used to use Bayer BioAdvanced Tree and Shrub pesticide, but now you cannot buy it in Colorado. I don't know why, especially when a cancer-causing we...
Knowledgebase
Why is this pesticide banned in Colorado #927844
Asked April 08, 2026, 3:37 PM EDT
I used to use Bayer BioAdvanced Tree and Shrub pesticide, but now you cannot buy it in Colorado. I don't know why, especially when a cancer-causing weed control chemical like Round Up is still available. Does anyone know why?
Larimer County Colorado
Expert Response
Hi Anthony,
The product you purchased contains imidacloprid, which is a neonicotinoid, and can have harmful effects on pollinators. It is now only available to purchase through licensed pesticide dealers.
Box stores can no longer sell it, but you can get it at independent stores, like garden centers.
Here's the list of licensed pesticide dealers and you can do a CTRL+F to search for your city: https://docs.google.com/spreadsheets/d/1VLYznIy7JaKeE8hbWTQ9K0hlLXt9v6fJUJdOyxvY7ss/edit?gid=51120080#gid=51120080
Also, Roundup has changed their formulations. Glyphosate is no longer available to homeowners in garden centers/box stores. The current formulation of Roundup is typically triclopyr ("tough brush killer") and fluazifop ("grass be gone").
The product you purchased contains imidacloprid, which is a neonicotinoid, and can have harmful effects on pollinators. It is now only available to purchase through licensed pesticide dealers.
Box stores can no longer sell it, but you can get it at independent stores, like garden centers.
Here's the list of licensed pesticide dealers and you can do a CTRL+F to search for your city: https://docs.google.com/spreadsheets/d/1VLYznIy7JaKeE8hbWTQ9K0hlLXt9v6fJUJdOyxvY7ss/edit?gid=51120080#gid=51120080
Also, Roundup has changed their formulations. Glyphosate is no longer available to homeowners in garden centers/box stores. The current formulation of Roundup is typically triclopyr ("tough brush killer") and fluazifop ("grass be gone").
