We’ve received many questions from our neighbors about Townsite’s plan to complete an aerial application of BTK and what it means for our community.
While the topic is sometimes contentious, we felt it was important to share our perspective. As residents of Redwood Meadows ourselves, we care deeply about the health of our forests and wanted to address some of the most common concerns.
Note: This is not an official Townsite or Council statement. Townsite will provide full information packages to residents. We are not entomologists or chemists—this article simply reflects what we’ve learned and the questions we’ve been asked by neighbors.
The spruce budworm is a caterpillar that primarily feeds on white spruce, the dominant tree species in our community.
After pupating, the caterpillars become moths, which lay eggs in spruce needles. These eggs stay dormant through the winter and hatch the following spring.
Once hatched, the larvae feed on new spruce buds and needles, building silk shelters for protection.
Timing is critical.
Early spring applications are not effective, as the larvae remain protected in silk clusters.
The most effective window is when the worms emerge from their silk shelters and begin feeding on fresh growth. At this stage, they are exposed enough to ingest BTK.
Unfortunately, this does mean the current year’s growth is usually lost—but research shows that protecting current growth does little to reduce budworm populations in the long run.
Years of infestation have left our trees visibly stressed:
Loss of new growth reduces the tree’s ability to stay healthy.
No spruce cones have been seen in years, meaning natural regeneration and reforestation are failing.
Dying branches allow disease to spread.
Hazardous dead trees now threaten homes and increase wildfire risks.
Without intervention, we face large-scale deforestation in our community.
BTK (Bacillus thuringiensis kurstaki) is a naturally occurring bacterium found in soil.
It only harms caterpillars (by ingestion) and is considered safe for humans, pets, wildlife, and most other insects.
BTK has been used worldwide since the 1960s for controlling harmful moth infestations.
Application is typically done via aerial spray, which is more effective and affordable than ground-based spraying.
Some residents have raised concerns after reading the Safety Data Sheet (SDS) for BTK, which mentions risks such as skin or eye irritation in its concentrated form. Here’s what’s important to understand:
These warnings apply to bulk concentrated BTK, not the diluted spray used in applications.
Once applied, concentrations are too low to cause irritation or environmental harm.
BTK breaks down naturally and does not accumulate in soil or waterways.
It is considered non-toxic to other plants and animals.
For residents with respiratory concerns, the recommendation is simple: close windows the night before spraying and stay indoors for about an hour after the application.
Some argue that budworms follow a “natural cycle” and will leave eventually. While technically true, they only leave once all available food is gone—meaning when the majority of our white spruce are dead.
Without BTK intervention:
We risk losing nearly all white spruce in Redwood Meadows.
Hazardous dead trees will increase significantly.
Wildfire danger will rise dramatically with so much dead fuel around homes.
BTK is safe, effective, and targeted specifically at caterpillars like the spruce budworm.
Townsite has engaged experts to ensure spraying happens at the optimal time for maximum effectiveness.
Without action, our community faces widespread tree death, loss of reforestation, and heightened wildfire risks.
Just as people sometimes need medical treatment, our trees now need this “prescribed intervention” to survive. BTK offers the best chance to restore balance, protect our forests, and preserve the natural beauty of Redwood Meadows.
Written by Sean Sterna – The Rocky Mountain Arborist | Used with Permission
Phone: (825) 945 8733
Email: Redmrig@outlook.com