European fruit lecanium (Brown apricot scale)
Parthenolecanium corni (Bouché)
Hemiptera: Sternorrhyncha: Coccidae
The adult female scale is nearly hemispherical and shiny brown, with several ridges along the back (A, arrow). Nymphs (crawlers) are light colored.
Most fruit-growing states and provinces in eastern North America.
Attacks all deciduous tree fruits, particularly peach. Female scales cover the undersides of twigs (B) and are most noticeable during the dormant season. Crawlers feed on the leaves throughout the summer and into the fall, covering the fruit with honeydew on which a sooty black fungus grows.
The terrapin scale, Mesolecanium nigrofasciatum (Pergande), is similar in biology and appearance (C), but slightly smaller than the European fruit lecanium and also has dark stripes radiating outward from the center.
Spray a delayed dormant oil when buds are showing green tissue but before pink bud to prevent development of eggs under the scale covers; an insecticide can be applied at the completion of crawler hatch 5–6 weeks after peach petal fall. However, soft scales (family Coccidae) are usually controlled by a complex of parasitic wasps; this can be facilitated by avoiding disruptive sprays.
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