🚨 Arborist Alert: 3 Alarming Tree Pests and Diseases in the Columbia Shuswap

The Telltale Signs Every CSRD Homeowner Needs to Spot

Your trees are some of your property’s most valuable and enduring assets. But in the Columbia Shuswap, our unique Interior Wetbelt and Interior Dry ecosystems host several pests and diseases capable of turning a healthy tree into a safety hazard in just one season.

As ISA Certified Arborists at Trees and Co. Arborist Services, we specialize in Plant Health Care (PHC)—catching issues before they become disasters.

Here is your essential guide to the three most common and dangerous threats to conifer and deciduous trees in the Salmon Arm, Revelstoke, and Sicamous areas, along with the telltale signs to watch for.

1. The Silent Killer: Root Rot

Root rot is arguably the most dangerous threat to urban trees because the main damage happens underground, leading to catastrophic tree failure (falling over) without much warning. It commonly affects many conifers, particularly Western Red Cedar and Hemlock.

Threat Level: High (Structural Risk)

The Telltale Signs:

• Fungal Bodies at the Base: Look for clusters of yellowish-to-honey-colored mushrooms growing near the base or along the root flare. This is a common sign of Armillaria root rot or Laminated root rot feeding on the decaying wood.

• Heaving or Cracked Soil: A tree whose root system is failing may show a slight, unusual lean or present with cracked, raised soil around the base of the trunk. This indicates the roots are no longer anchoring the tree firmly.

• Thinning Crown: The tree canopy will gradually decline, thinning out from the top down. The tree may produce a “stress crop” of extra cones or prematurely turn yellow/brown.

What to Do Now:

If you see fungal growth or soil heaving, call us immediately. A decayed root system cannot be fixed, but a risk assessment can determine the tree's stability. In many cases, timely removal of an infected, high-risk tree is the only way to protect your home and prevent the disease from spreading to adjacent healthy trees through root contact.

2. The Conifer Crisis: Bark Beetles

Bark beetles—including the Douglas-fir Beetle and the Mountain Pine Beetle—are naturally occurring insects that attack stressed trees. Once a beetle successfully tunnels past the bark and into the vascular tissue, the clock starts ticking for your tree.

Threat Level: Extreme (Rapid Mortality)

The Telltale Signs:

• Pitch Tubes: On Pine and Douglas-fir trees, look for small, sticky, popcorn-like lumps of reddish-white sap on the bark. This is the tree attempting to push the invading beetle out.

• Reddish-Brown Frass: Find fine, reddish-brown sawdust (called "frass") caught in bark crevices or near the base. This is the material the beetle pushes out as it tunnels.

• Needle Colour Change: The first outward sign is often the rapid, uniform change of the needles from green to orange-red or brown across the entire crown. This happens when the fungi the beetles carry stops the tree from transporting water.

What to Do Now:

If you suspect a beetle infestation, time is critical. We use specialized, site-specific injections or sprays to protect healthy trees nearby. For infested trees, safe removal is often necessary to stop them from becoming a breeding ground that puts your neighbours' trees at risk.

3. The Deciduous Defoliator: Large Aspen Tortrix & Leaf Miner

These native insect pests target broadleaf trees common in the Shuswap, like Trembling Aspen and Poplar. While they rarely kill a healthy, mature tree outright, they severely impact its vitality.

Threat Level: Moderate (Health & Appearance)

The Telltale Signs:

• Webbing and Chewed Leaves: Look for leaves that have been rolled, tied together with fine silken threads, or are heavily skeletonized (chewed down to the veins).

• Premature Defoliation: In severe outbreaks, the tree can lose most of its leaves by mid-summer.

• Serpentine Trails: For the Aspen Leaf Miner, you may see visible, winding, discoloured tunnels ("serpentine trails") inside the leaf tissue.

What to Do Now:

These pests typically occur in cyclical outbreaks. While chemical control is sometimes used for high-value ornamental trees, the best long-term defense is tree health. Ensure your Aspens and Poplars are properly watered and are not suffering from drought stress. We can provide targeted insect management plans to protect your most prized specimens.

The Certified Arborist Advantage

Tree pests and diseases move fast, but the initial symptoms can be subtle. Waiting for a large dead branch or a severe lean is often waiting too long.

A Trees and Co. Arborist Services Plant Health Care inspection pinpoints early signs of stress long before they become visible to the average eye. We diagnose the true cause of the problem and create a customized treatment plan based on the specific conditions of your Columbia Shuswap property.

Don’t leave the health and safety of your trees to chance. Call us today.