Gary W. Moorman, Professor of Plant Pathology
|Dieback and canker||Leaves wilt and die as branches are slowly killed. Small, sunken cankers slowly increase in size. The wood beneath the canker is discolored. Trees cankered near the base will die.||Botryosphaeria||Prune infected branches well below the canker. Remove severely infected trees. Protect trees from drought stress and winter injury.|
| Fire blight ||Twigs, branches, and leaders on shrubs wilt and blacken, especially during flowering. Affected twigs and branches may bend over into the shape of a shepherd’s crook. Blackened flower parts remain attached to the plant. Cream-colored liquid may ooze out of the cankers and run down the trunk and branches in the spring if conditions are very wet. No fungal fruiting structures are found in the cankers|| Erwinia amylovora ||Pyracantha cultivars considered resistant include Mojave, Shawnee, and Yunan. Do not purchase or plant infected material. Remove severely infected plants. During dormancy when the weather is dry, prune infected branches, cutting at least 4 inches below the base of the canker. Disinfest pruning tools frequently.|
|Scab||Velvety, olive green spots can form on all plant parts. Leaves and fruit fall prematurely.||Spilocaea pyracanthae (Fusicladium)||Plant resistant cultivars such as Bella, Duval, Flava, Firey Cascade, Government Red, Prostrata, Rutgers Shawnee, and Santa Cruz Prostrata. Avoid using sprinkler irrigation. Apply a fungicide in the spring and at regular intervals until the weather dries.|
Scab on foliage and fruit.
Notice: The user of this information assumes all risks for personal injury or property damage.
Warning! Pesticides are poisonous. Read and follow all directions and safety precautions on labels. Handle carefully and store in original labeled containers out of the reach of children, pets, and livestock. Dispose of empty containers right away, in a safe manner and place. Do not contaminate forage, streams or ponds.
Issued in furtherance of Cooperative Extension work, Acts of Congress, May 8 and June 30, 1914, in cooperation with the U. S. Department of Penn State College of Agricultural Sciences research and extension programs are funded in part by Pennsylvania counties, the Commonwealth of Pennsylvania, and the U.S. Department of Agriculture.
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