Blog Archives

Bacterial Leaf Scorch Can Torch Landscape Trees

Kentucky’s landscapes are populated by many trees that are susceptible to bacterial leaf scorch. This disease may not kill trees instantly, but over time, it can have devastating effects. Pruning and reducing stress can prolong the life of infected trees;

Posted in Landscape Trees & Shrubs

How Dry Seasons Affect Woody Plants

Water is an essential component to plant mass and is vital to growth, carbohydrate production, and nutrient transport. During periods of below-average rainfall or when rain distribution is uneven, plant health may decline (Figure 1). Drought conditions or inadequate water

Posted in Landscape Trees & Shrubs

Stress and Decline in Woody Plants

Woody trees and shrubs may exhibit decline resulting from the stresses that can occur during their lives. Stress may be the result of improper plant or site selection, incorrect planting or maintenance practices, or poor soil conditions. Injury from equipment,

Posted in Landscape Trees & Shrubs

Boxwood Blight

Boxwood blight can be devastating to American boxwood cultivars, which are common in the Kentucky landscape. Complete defoliation can occur within a week and plants can die within a single growing season. Use of tolerant cultivars, cultural practices, and fungicides

Posted in Landscape Trees & Shrubs

Dogwood Powdery Mildew

Dogwood is a popular landscape tree throughout Kentucky. However, once infected with powdery mildew, trees can develop an unattractive appearance. The disease is most prevalent during periods of high humidity and in landscapes with reduced air circulation. Some cultivars are

Posted in Landscape Trees & Shrubs

Laurel Wilt Disease: A Threat to Kentucky Sassafras Trees

Laurel wilt is a new disease that was recently detected in southwestern Kentucky. This disease, which is transmitted by the redbay ambrosia beetle, has the potential to rapidly kill sassafras trees. Currently no management options are available for this disease.

Posted in Forest Trees, Landscape Trees & Shrubs

My Trees Have Lice!

Barklice that is. While that sounds alarming, and brings to mind blood-sucking lice, barklice are not lice and are very different from the parasitic lice that can infest people and livestock. Barklice cause concern when they are seen in large

Posted in Landscape Trees & Shrubs

Hanging by a Thread

Dead, curled leaves dangling by fungal “threads” are typical of a disease called thread blight.  This disease is more common in eastern Kentucky, where it has been observed on apple, cherry, and viburnum.  Other potential hosts include cotoneaster, dogwood, gooseberry,

Posted in Fruit, Landscape Trees & Shrubs

Cherry Leaf Spot

Cherry leaf spot is a fungal disease of sweet, sour, and ornamental cherries. While this leaf disease is rarely a death sentence for trees, it can result in reduced blossoms, weakened trees, and increased risk for winter injury. Cherry Leaf

Posted in Fruit, Landscape Trees & Shrubs

Dieback in Landscape Trees – Could it be Verticillium Wilt?

The stress of hot, dry conditions in midsummer can prompt leaf scorch in many landscape trees. However, extensive canopy dieback or tree collapse, particularly on one side of a tree, may indicate Verticillium wilt disease.  Numerous cases of this vascular

Posted in Landscape Trees & Shrubs

Rhizosphaera Needle Cast May Lead to Skimpy Spruce

Rhizosphaera needle cast is often to blame for brown or thin spruce in the landscape. In Kentucky, Rhizosphaera needle cast is the most common disease of spruce; it also affects some pine species. This disease causes needle drop on lower

Posted in Landscape Trees & Shrubs

Congrats, It’s a Baby Bagworm!

Bagworm season is upon us in Kentucky. Depending on where you live, the hatching could have occurred anywhere from just in the last few days to a couple of weeks ago. If you want to monitor for their emergence next

Posted in Landscape Trees & Shrubs

Spruce Dieback – Needle Cast Diseases May Be To Blame

Blue spruce and Norway spruce are popular landscape plants in Kentucky. However, many factors can cause spruce trees to cast (shed) needles. Casting may be the result of environmental stresses (heavy soil, poor drainage) or fungal diseases. In Kentucky, Rhizosphaera

Posted in Landscape Trees & Shrubs

Anthracnose Diseases on Shade Trees

The term anthracnose refers to the dark blotching (necrotic) symptom common to these diseases.  When expanding leaves are affected, leaf distortion frequently results (Figure 1). Defoliation (leaf drop) often occurs during severe infections. The disease is generally not fatal, and

Posted in Landscape Trees & Shrubs

The Dark Side of Black Root Rot in Ornamentals

Black root rot can affect a wide range of ornamentals in home and commercial landscapes, nurseries, and greenhouses. Black root rot is commonly observed on Japanese and blue hollies, inkberry, pansy, petunia, and vinca. Black Root Rot Facts Symptoms are

Posted in Landscape Trees & Shrubs, Ornamentals