Necrotic Ring Spot

Necrotic Ring Spot Occurrence: Late winter, spring, and fall. Most severe on Kentucky bluegrass, annual bluegrass, and creeping red fescue. Irregular patches of grass with various shades of yellow, tan, or brown “rings” and green grass in the center. The size of the individual patches of dead grass range from 2-3 inches to 2-6 feet in diameter. ...

Summer Patch

Occurrence: Summer There are no distinctive leaf lesions associated with summer patch. The disease first appears as faded, wilted or reddish-brown patches of grass 2-6 inches in diameter. These patches fade to light brown rapidly as the leaves wither and die. The individual patches may expand to 12 inches in diameter. Conditions Favoring Disease ...

Fairy Ring

Occurrence: Rings or arcs of deep green grass as well as unhealthy or dead grass. Rings may vary in size from a few inches to 200 feet or more indiameter with an annual radial growth of 3 inches to 19 inches depending on grass, soil and weather conditions. Mushrooms may appear in the rings or arcs. Mycelium in the soil is evidence that the fungus...

Rust

Occurrence: Primarily late summer and early fall. However, rust can occur during spring, late fall and throughout the winter months if air temperatures are moderate. Leaf lesions beginning as light yellow flecks. The lesions develop into reddish-brown pustules and yellow, red or brown spores. Leaves of the affected plants may turn yellow, beginning...

Powdery Mildew - Lawn

Occurrence: Shaded areas during spring, summer, and early fall. Distinctive disease growth on surface of the leaves of fine, gray-white, talcum powder usually on the upper surface of the leaves. The growth rapidly becomes dense and may cover the entire leaf. As colonization of the leaves by the pathogen increases, the leaf develops chlorotic ...

Powdery Mildew - Tree/Shrub

Occurrence: Shaded areas with poor air flow during spring, summer, and early fall. Distinctive disease growth on surface of the leaves of fine, gray-white, talcum powder usually on the upper surface of the leaves. The growth rapidly becomes dense and may cover the entire leaf. onditions Favoring Disease Development: Poor air circulation with high ...

Leaf Gail

Occurrence: During active growing season when insect pressure exists. Leaf galls are bumps and deformations usually resulting from insects feeding on the leaves. The gall is the plant's response to the irritation. By the time you see the gall, the insect has moved on. The gall is not going to go away until the end of the season when the tree loses ...

Leaf Spot

Occurrence: Spots usually become noticeable from late June through August. The fungi is present throughout the growing season. Leaf spot are caused by a fungus infections that may start early in the growing season and can lead to premature defoliation. The disease is spread by the production of microscopic spores from early spring into summer and ...

Fire Blight

Caused by bacteria, fire blight is a common and frequently destructive disease. It primarily affects pear, but apple and crabapple are also susceptible. Fire blight is less common on hawthorn, spiraea, ash, and other related plants. The disease can destroy limbs or entire shrubs or trees. Branch and trunk canker symptoms can appear as soon as the ...

Verticillium Wilt

Occurrence: Symptoms develop during the growing season, but usually appear in July and August. Verticillium wilt is caused a soil-borne fungi which is common in many soils and affects several hundred plant species including Ash, Dogwood, Plum, Azalea, Redbud, Barberry, Elm, Rose, Boxwood, Honeysuckle, Lilac, Catalpa, Linden, Smoke tree, Cherry, ...

Root Rot (Phytophthora, Phythium, Armillaria)

Occurrence: Develops gradually over a period of month or years. Root rot results from infection by any of three soil-borne fungi. Phytophthora, Phythium , and Armillaria root rots spread most quickly in warm, moist conditions. Phytophthora limits the amount of moisture and nutrients the plant can absorb. Affected plants become weak with wilting, ...