Fruit tree canker

Susceptibility fruit tree canker, lenticel blotch pit... 

Areas of application Scab, fruit tree canker... 

Fruit trees infected by fire blight benefit from pruning that removes blighted twigs and disease cankers and stimulates air flow through the branches. 

Signs Plants infected with citrus canker have characteristic lesions on leaves, stems, and fruit with raised, brown water-soaked margins usually with a yellow hallow effect around the lesion. Incubation is typically 14-60 days. Older lesions may fall out, creating a shot-hole effect. Fruit production declines and then stops. The disease ultimately kills the tree. 

What to do Prune out affected branches and remove fruit from the tree. Pick up windfalls. Do not compost any of this material. Take care not to damage fruit that is to be stored. Do not store any diseased fruit. Prune out cankers and diseased spurs. 

Symptoms Tree bark shrinks and cracks, often in concentric rings with the central piece of bark falling away. Deep lesions develop on the branches. Swelling can occur around the canker, and young twigs may die back. Cream-colored pustules may be seen in summer red spots are more common in fall. Papery bark can result Canker can ring an entire stem. Fruit skins crack fruits dry and can remain, mummified, on the tree. 

Symptoms Infected fruit shows small brown spots that often enlarge to cover the surface. These patches produce masses of grayish brown spores. The fruit eventually rots and shrivels up (forming a mummy) the damaged fruit may drop or persist in the tree. Small cankers may form on branch tips. Early in the season, flowers may be infected for more details, see Brown Rot on page 386. 

Symptoms Flowers usually show symptoms first, browning and shriveling. Leaves turn brown or black. Dead leaves remain on twigs. Symptoms progress from the tips of shoots toward the roots. Shoot tips turn black, wilt, and curl downward. Cankers form on branches. Fruit turns black and may cling to the tree. 

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