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  • Integrated Pest Management
  • Protecting Pollinators
  • Invasive Species
  • Reducing Pesticides
  • Mosquito Control Program
  • Natural Lawns and Landscaping

Weeds, Rats and Tree Pests - Making Sense of Invasive Species

All invasive species have one thing in common, whether it's a mammal, insect, weed, fungus or virus. They are non-native to local ecosystems and have the potential to cause harm by out-competing native plants, animals or resources, or causing disease to humans, wildlife or plants. Some non-native or non-local species are thought to cause little harm to ecosystems, but others can have devastating impacts. Emerald ash borer is an example of how destructive an invasive insect can be and a perfect illustration as to why. Ash trees in their native range in Asia evolved with emerald ash borer and developed resistance. Predators and diseases also evolved that attack emerald ash borer to keep populations in check. With none of those limiting factors in place, infestation with emerald ash borer is 100 percent fatal to American ash trees without systemic insecticide treatments and has killed millions of trees as it spreads across the country. 

Some invasive species are accidently transported to a new location, like rats, insect pests or weed seeds. But some are purposely brought to a new area and then escape to wild lands or spread unchecked for the same reasons of accidentally-introduced species. Some of the noxious weed species that are threatening native ecosystems were brought as ornamental plants, such as purple loosestrife. Others were brought as forage, like Japanese knotweed. Learn more about how to manage weeds, rats, and emerald ash borer below. 

Emerald Ash BorerEmerald Ash Borer

Learn more about Emerald Ash Borer in Boulder and what you can do about it. 


Managing WeedsRemoving Weeds From Your Property

Learn which weeds you're required to remove from your property by state law and how to do it without chemicals.




A Guide for Safe and Effective Rat Control

An online guide about what to do to keep rats out of your home or business--and what to do if they're already there.