Dead trees or portions of trees are structurally unsound and their time of failure is unpredictable.

Any dead tree, dead branch, dead top or lodged branch.

A split through the bark, extending into the wood. Wood fibers are not fused. Cracked stems or branches cause the affected area to act as 2 or more separate beams, weakening mechanical support.

1. Crack goes completely through a stem or is > 6’ long.

2. Two cracks occur on the same stem segment.

3. The stem has a crack in contact with another defect such as decay, a canker or weak union.

4. A cracked branch

Wood that is missing or structurally compromised.

1. Decayed wood or cavity affects ½ or more of the stem’s circumference.

2. There is less than 1” of sound wood for every 6” in stem diameter.

3. Any tree infected with a canker-rot fungus.

Union with ingrown bark between stems; wood fibers are not fused. Weak unions are characterized by an acute angle between stems.

Tight union that is either cracked or decayed or associated with another defect.

Localized area of dead bark and cambium; wood behind canker may or may not be decayed. Commonly caused by fungi or mechanical injury.

Canker affects ½ or more than the stem’s circumference.

A growth pattern or structural imbalance that causes a weakness.

1. Structural imbalance associated with a weakness (typically decay).

2. Tree with an excessive lean (>45).

3. Large defective branches. Defect may include sharp bend or twist or inrolled bark.

Loss of structural support due to root rot, wounding, severing or any other factors that causes root mortality.

1. More than 45% of roots severed or otherwise compromised.

2. Leaning tree with recent root lifting.