Tree and Shrub Diseases

This disease will cause brown, dry, blotchy spots on the leaves and may cause the leaves to drop

Apple scab causes apple and crabapple trees to drop their leaves early in the late spring and early summer. The leaves will have black and brown spots all over

On the twigs, you’ll see a soft olive green growth and it will change to hard black knots in the fall. Large clumps of bark swell on the ends of branches and twigs of the tree. This disease mostly attacks fruit and branches. This disease is life threatening if not treated.

The symptoms of this disease are yellow or orange-brown to black discolored areas on the bark of the trunk and branches. The needles turn brown and the lower branches die back.

The affected trees will show needles turning brown to gray at the tips. This may lead to an attack on the twigs and branches. The ends of the pines curl up and turn brown, typically on the lower branches of the pines.

A leaf spot disease creates spots on foliage. Spots are most often brownish, but may be tan or black. Concentric rings or a dark margin around the spot may be present. Trees and shrubs will have dark spotting on the leaves.

Infected needles usually turn red to brown from their tips beginning in winter or early spring. By mid to late spring the death of infected needles is well advanced giving diseased trees a red to brown "fire-scorched" appearance.

The disease is most active when new growth is wet. Normally the disease attacks in the spring. The new growth will turn brown and when the disease progresses too far, the plant cannot be saved.

The leaves will appear to have a white or gray film in the late summer causing the leave to turn brown and drop early. The wind can blow spores from leaf to leaf.

All rust fungi produce powdery masses of spores, typically on leaf undersides that are yellow, orange, purple, black or brown. Some rust fungi produce pustules on upper leaf surfaces as well.

The first symptoms of infection by a tar spot fungus usually show up in mid-June as small, pale yellow spots. The spots enlarge and their yellow color intensifies as the season progresses.

The leaves of the tree will look like they’ve been scorched and start to fall. The branches will start to die-back. This disease can kill a healthy Norway maple in just one season.