News

Weed of the Month: Bittersweet Nightshade

For this Weed of the Month, we’re bringing bittersweet nightshade into the light. Here are some tips for identifying and managing infestations to protect your family, pets, and livestock from this toxic invader.

Herbicide Physiology and Classifications

Herbicides are chemicals that are phytotoxic to plants. As with the medicines that we take to get better, herbicides must be applied to undesirable and invasive plants in the right method, at the right dose, and at the right time to be effective in eradicating.

Weed of the Month: Dyer's Woad

This Weed of the Month, we’re covering dyer’s woad. If you’ve ever seen a yellow burst alongside the road or trail, there’s a good chance you were looking at dyer’s woad! This mustard-family invader can start as a low, easy-to-miss rosette, then it quickly shoots up and fills open ground with flowers and seed pods. Timing is essential: once it seeds, it gets a lot harder to stay ahead of; early action is vital to keep this pest at bay.

Weed of the Month: Spotted Knapweed

This month, we’d love your help spotting Spotted Knapweed! This thistle lookalike has no spines, a deep taproot, and an affinity for turning wildlife diversity into a one-plant show. Once it shows up and makes itself home, it pushes out the locals that wildlife and livestock love and rely on.

Detection and Management Strategies for Insecticide Resistant Mosquitoes

West Nile virus (WNV) is the most significant mosquito-borne disease in Wyoming, with Culex tarsalis serving as the primary vector statewide. In 2023, Wyoming experienced nearly three times the number of human WNV cases compared to any year in the previous decade, with most cases linked to in-state exposure. During outbreaks like these, adulticide applications become a critical tool for reducing infectious mosquito populations near people.However, adulticides rely on a very limited number of insecticide classes. Repeated use — even at low frequencies — creates strong selection pressure, allowing resistant mosquitoes to survive and pass resistance traits to future generations.

Range Expansion of the American Dog Tick

Ticks are responsible for over 95% of vector-borne disease cases in the United States, yet historically, very little tick surveillance has occurred in Wyoming. As tick-borne diseases increase nationwide and tick ranges continue to expand, understanding which tick species and pathogens are present in Wyoming is becoming increasingly important for public and animal health.

Weed of the Month: Poison Hemlock

For this Weed of the Month, we’re talking about poison hemlock. This invasive weed is pretty, prolific, and (surprise, surprise) poisonous! A member of the carrot family, this biennial loves to show up where we live and play, spreading quietly into problem patches for pets, livestock, and loved ones. Unlike carrots, this one is no good in stew.

Your Property Taxes at Work

Teton County Weed & Pest Control District (TCWP) is a statutorily mandated special district funded through a dedicated property tax mill levy. Governed by a board appointed by the county commission, TCWP operates independently of the county general fund to carry out invasive species management and vector-borne disease prevention. TCWP’s mission is to protect and restore ecosystem health while safeguarding public well-being. In 2025, the district employed 9 full-time staff and 16 seasonal employees, whose efforts are essential to field operations, monitoring, and community programs. Together, this team works to support a healthy environment and empowered community across Teton County.

NISAW: Defending Our Health By Stopping the Spread

Invasive species are a worldwide threat, posing danger not just to wildlife and our environment, but to agriculture, economies, and our very health. National Invasive Species Awareness Week (NISAW) is an annual campaign led by The North American Invasive Species Management Association (NAISMA) that’s dedicated to shining a spotlight on the widespread damage caused by invasive species and how we can work together to stop them.

Lab Safety

At TCWP, we have a BSL- 2 (Biological Safety Level 2) lab that allows us to test for various pathogens in common vectors, including mosquitoes within 24-48 hours of collection for West Nile Virus and ticks for Colorado Tick Fever Virus (CTFV), and more. As the workload on our lab and team increases, so do the hazards. We’re proud of the safety protocols we have in place that protect our team and the community. Learn more about how Lab Safety keeps our team and mission running responsibly.