Apple Scab

Apple scab is a potentially serious fungal disease of ornamental and fruit trees in the rose family. This factsheet describes symptoms, management and control of this sometimes serious disease.

Roseslug Sawfly

Roseslug sawfly causes damage to leaves of wild and cultivated roses in early summer. This factsheet will help you identify this insect and manage the damage it causes.

Root and Crown Rots

This factsheet covers root/crown rot, which is a general term that describes disease of woody ornamentals where the causal organism attacks a plant’s root system and/or lower trunk or branches near the soil.

Purple Bordered Leaf Spot

Purple-bordered leaf spot (also called eye spot or Phyllosticta leaf spot) is a common, but mostly cosmetic, disease on maples. This factsheet describes symptoms and management.

Magnolia Scale

Magnolia scale sucks plant sap and excretes drippy, sticky honeydew which can turn black with mold growth. Learn more, including control, in this factsheet.

Guignardia Leaf Spot

Guignardia leaf spot is a fungal leaf spot that affects vining plants such as Boston ivy and Virginia-creeper, and is associated with a leaf spot and fruit rot of grape called black rot. Learn more here.

Golden Canker (Cryptodiaporthe Canker)

Golden canker is a visually distinct and common disease of alternate-leafed dogwoods such as pagoda dogwood, which can be lethal if on the main trunk of a tree. Learn more in this factsheet.

Euonymus Scale

Euonymus scale attacks evergreen shrub and vine forms of euonymus, along with privet, bittersweet and pachysandra. Learn to identify and manage euonymus scale in this factsheet.

Dutch Elm Disease

Dutch elm disease is a lethal fungal disease of native elms. This factsheet describes symptoms, spread and management of this serious disease.

Boxelder Bugs

Though not really harmful to plants, box elder bugs become a nuisance when coming indoors in fall. This factsheet describes the life cycle and habits of box elder bugs.

Black Walnut Toxicity

Black walnut trees produce a toxic substance (called juglone) that prevents many plants from growing under or near them. Learn more about this compound and how to work around it in this factsheet.

Ash Flower Gall

Tiny eriophyid mites can cause male flowers and leaf distortions on ash trees. While unsightly, tree health is not adversely affected. Learn more here.

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