Pest detection and control guide
Tree Pest & Disease Awareness Guide
Suspect a pest? We're here to help!
We’re a Clean Plants Certified Nursery
At Alberta Tree Farms, we take pride in growing healthy, pest-free trees, shrubs, and perennials. We are Clean Plants Certified, meaning we follow nationally approved best practices and maintain a rigorous pest management program to ensure:
- Disease-free stock
- Healthy root systems
- Early detection of threats
- Proper sanitation & handling practices
Your success starts with clean, strong trees — and we’re here to help keep them that way.
Common Pests to Watch for in Alberta
Here are some of the most common pests you might encounter in Alberta. This guide is meant to help you recognize early signs, not to diagnose or treat. Always contact a professional or reach out to our team for support.
🐞 Aphids
Affects: Deciduous trees (Ash, Elm, Maple), shrubs, perennials
Signs: Sticky leaves (honeydew), curling leaves, sooty mold
Tips: Hose down with water for mild cases. Avoid over-fertilizing (aphids love soft new growth).
🐛 Leafrollers
Affects: Apple, poplar, and willow trees
Signs: Leaves curled and webbed together with silk; larvae inside
Tips: Prune infested twigs early. Encourage natural predators (birds, ladybugs).
🕷 Spider Mites
Affects: Spruce, pine, juniper, and ornamental shrubs
Signs: Yellow or bronze speckling on needles/leaves; fine webbing
Tips: Mites thrive in hot, dry weather — spray trees with water during heatwaves to discourage them.
🐞 Elm Leaf Beetles
Affects: Elm trees (especially Brandon Elm)
Signs: Skeletonized or browning leaves
Tips: Rake up and destroy fallen leaves in fall to interrupt their lifecycle.
🐞 Bronze Birch Borer
Affects: Birch trees
Signs: Dieback in upper branches, D-shaped exit holes in bark
Tips: Keep trees healthy — borers target stressed trees. Prune dead limbs in fall or winter.
🐛 Mountain Pine Beetle
Affects: Lodgepole and Ponderosa Pine
Signs: Popcorn-shaped sap masses on bark, yellowing needles, woodpecker activity
Tips: Preventative tree health is key. Infected trees often need removal by professionals.
🐞 Cottony Psyllid
Affects: Swedish Columnar Aspen
Signs: Leaves curl inward with white fuzz inside
Tips: Difficult to treat without systemic sprays. Reach out to a licensed applicator.
⚠️ A Word on Safety: Don't Spray Without a License
Never apply chemical sprays, pesticides, or fungicides unless you're licensed to do so.
Incorrect or illegal use can:
- Harm your tree
- Damage beneficial insects
- Contaminate soil or groundwater
- Violate Alberta pesticide regulations
When in Doubt — Call Us or a Certified Arborist
We are happy to offer guidance on pest identification and next steps.
If you think your tree is affected by a pest or disease:
- Take clear photos
- Note the type of tree and location
- Contact us directly or consult a licensed tree care professional
Proactive Tree Health Tips
✅ Mulch properly to retain soil moisture and insulate roots
✅ Avoid overwatering or over-fertilizing — stressed trees attract pests
✅ Inspect regularly for changes in bark, leaf color, or insect activity
✅ Keep tools clean between trees and planting jobs
✅ Rake leaves in fall to remove eggs and overwintering insects
Our Pest Management Program
At Alberta Tree Farms, our internal program includes:
- Weekly visual inspections
- Clean Plants audit compliance
- Monitoring for regulated pests
- Best-practice pruning and sanitation
- Zero-tolerance on invasive species
We’re committed to delivering trees you can trust.
