As spring arrives in Colorado, it brings new life and growth to our landscapes. However, it also heralds the emergence of common pests that pose a significant threat to the health and vitality of our beloved trees. At Front Range Arborists, we recognize the urgency of proactive pest management to safeguard your trees and ensure their longevity. Early intervention is crucial – here are some of the most common spring tree pests in Colorado, along with effective methods for identification and treatment.

Emerald Ash Borer (EAB)

The emerald ash borer is an invasive beetle that poses a significant threat to ash trees in Colorado. As temperatures warm in the spring, adult beetles emerge from infested trees and seek new hosts. Signs of an emerald ash borer infestation include D-shaped exit holes in the bark, canopy dieback, and epicormic sprouting. If left untreated, EAB infestations can lead to the decline and eventual death of ash trees. Treatment options include systemic insecticides injected into the tree’s trunk to protect against infestation.

Pine Bark Beetles

Pine bark beetles are another common pest found in Colorado forests and landscapes. These tiny insects burrow beneath the bark of pine trees, disrupting the tree’s nutrient transport system and causing damage that can ultimately lead to tree death. Symptoms of a pine bark beetle infestation include yellowing or browning needles, pitch tubes on the trunk, and sawdust-like frass near the base of the tree. Early detection and prompt treatment with insecticides can help prevent the spread of pine bark beetles and preserve the health of affected trees.

Tent Caterpillars

Tent caterpillars are a nuisance pest that can defoliate trees and shrubs in the spring. These caterpillars construct silken tents in the branches of host trees, where they feed on foliage and cause significant damage. Common host plants include fruit trees, aspen, and cottonwood. To control tent caterpillars, physical removal of the tents and larvae can be effective, along with the application of insecticidal sprays to target feeding caterpillars.

Aphids

Aphids are small, sap-sucking insects that can infest various trees and ornamental plants in Colorado. These pests reproduce rapidly and can quickly cause damage to new growth, leading to stunted growth, distorted leaves, and honeydew secretion. Ladybugs and lacewings are natural predators of aphids and can help keep populations in check. Additionally, horticultural oils or insecticidal soaps can be applied to foliage to control aphid infestations.

Powdery Mildew

Powdery mildew is a fungal disease that commonly affects trees and shrubs in Colorado, particularly during periods of cool, damp weather in the spring. This disease appears as a white or gray powdery coating on the leaves, stems, and buds of infected plants. Powdery mildew can weaken trees and make them more susceptible to other pests and diseases. To prevent powdery mildew, ensure proper spacing between plants to promote air circulation and avoid overhead watering, which can create conditions favorable for fungal growth.

As spring arrives in Colorado, it is essential to be vigilant in identifying and treating common tree pests to protect the health and vitality of your landscape. At Front Range Arborists, our team of experts specializes in pest management and tree care services tailored to the unique needs of Colorado trees. Whether you are dealing with emerald ash borers, pine bark beetles, tent caterpillars, aphids, or powdery mildew, we are here to help. Contact us today to schedule a consultation and safeguard your trees against pests this spring and beyond.