Plant Diagnostics

Lecanium scale - Parthenolecanium species

Description

Family comprised of more than a dozen species of soft scales that are difficult to distinguish from one another but this group has no waxy covering, and lengths of 3-12 mm. Once females lay their eggs her hemispherical body dries and become brown.

Damage

Most frequent activity and feeding occurs in the spring and early summer when eggs hatch and and crawlers migrate to leaves.

Remarks

Treat crawlers when Hydrangea arborescens 'Grandiflora' is in full bloom (900-1200 GDD).; make a second application 2 weeks later. Apply chlothianidin, dinotefuran, imidacloprid or thiamethoxam as a soil injection or drench in the fall. Spring applications should be made foliarly. Apply lime sulfer during the dormant season only.

Chemical Controls

carbaryl
Signal Word: Warning
Pesticide Class: carbamate
chlorpyrifos
Signal Word: Caution
Pesticide Class: organophosphate
chlothianidin
Signal Word: Caution
Pesticide Class: neonicitinoid
deltamethrin
Signal Word: Caution
Pesticide Class: Synthetic pyrethroid
dinotefuran
Signal Word: Caution
Pesticide Class: neonicitinoid
imidacloprid
Signal Word: Caution
Pesticide Class: chloronicitinoid
lime sulfer
Signal Word: Danger
Pesticide Class: sulfur
thiamethoxam
Signal Word: Caution
Pesticide Class: neonicitinoid
ultra-fine oil
Signal Word: Caution
Pesticide Class: horticultural oil

Locations Affected

branches

Scouting Season:

July - Early , July - Mid , July - Late , August - Early

Plants Affected


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