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Problem
(factsheet)
Plant NameTypeDescription 
Leaf spotPieris (Andromeda)DiseaseLeaf spot of andromeda is a fungal disease causing necrotic (dead) spots on the leaves. Spots are circular or angular in outline, and typically are red to brown, sometimes with silvery-gray centers. Fruiting structures of the fungus may occasionally be seen as small black dots on the silvery portion of the spots.
Ramorum leaf and shoot blight (Sudden oak death)Pieris (Andromeda)DiseaseRamorum leaf blight is caused by Phytophthora ramorum, the same organism that causes sudden oak death (SOD). In Washington, most cases have been found in nurseries on rhododendrons and camellias, which are highly susceptible to this disease. Some oak species, viburnum, and kalmia are also considered highly susceptible, along with native plants such as salal and evergreen huckleberry. On Pieris, leaves and shoots are blighted and killed. Damaged tissues turn dark brown and wilt, remaining attached to the plant. Damage is usually most severe to the youngest (topmost) parts of the plants. Infection on older leaves may be limited to dieback of leaf tips. Symptoms of this disease may strongly resemble those caused by sunscald, chemical damage, or cold injury, making field diagnosis difficult. IT IS NOT POSSIBLE TO CONCLUSIVELY DIAGNOSE THIS PROBLEM BASED ON VISIBLE SYMPTOMS ONLY. In Washington, Ramorum leaf blight has so far been found only in association with infected nursery plants and water runoff from infected nursery sites. While this disease has the potential to become a serious and economically significant problem, it is not yet considered to be widespread in Washington in either cultivated or native landscapes. P. ramorum infection is NOT LIKELY in the landscape UNLESS the plant (1) is a highly susceptible species AND (2) was purchased since 2002 AND (3) is showing symptoms associated with P. ramorum infection (or is located near another plant that meets all these criteria). Currently, the only way to confirm a SOD diagnosis is with laboratory tests.
Root rot & diebackPieris (Andromeda)DiseaseRoot rot and dieback of andromeda is caused by Phytophthora, a fungus which affects many ornamentals. Typically, plants appear unhealthy, with wilted or discolored leaves that may be stunted or drop prematurely. The fungus attacks the roots and progresses to the crown, eventually killing the plant. It is most frequently a problem in waterlogged or poorly drained soils. This disease can be spread by water movement or by root contact between diseased and healthy plants.
Black vine weevilPieris (Andromeda)InsectCharacteristic damage by black vine weevils includes irregular, ragged notching of leaf margins by adults and minor to severe root and bark damage by larvae. The adult is a gray to black beetle about 2/5" long which feeds at night. The larvae feed below ground on roots or just beneath the soil surface on the bark at the crown of the plant. Bark feeding can result in girdling and plant death.