Plant Diagnostics

Soft scale - Coccidae family

Description

Soft scales are usually broadly oval becoming larger and more humped as eggs mature underneath the protective cover. Look for adults on twigs or small branches and immature stages on leaves or needles.

Damage

Yellowed leaves and distorted foliage are indications of scale infestations. Soft scales produce honeydew, which is one of the first signs of infestation. Another sign is ants feeding on the honeydew and the presence of sooty mold.

Cultural Controls

Inspect leaf undersides and stems frequently for the presence of scales. Remove and destroy heavily infested plants. Wash off honeydew and dislodge crawlers with water sprays. Inspect all new plant material on arrival. Hand pruning may be useful to remove small infestations.

Remarks

Apply clothianidin, dinotefuran, imidacloprid, or thiamethoxam as a soil injection or drench in the fall. Horticultural oils and soaps are very effective for soft scale control throughout much of their life, especially when they are young. Dormant oils should only be used after plants have hardened off in the fall and before buds swell in the spring.

Chemical Controls

Acephate
Signal Word: Caution
Pesticide Class: Organophosphate
Azadirachtin
Signal Word: Caution
Pesticide Class:
Bifenthrin
Signal Word: Caution
Pesticide Class: Synthetic pyrethroid
Buprofezin
Signal Word: Caution
Pesticide Class: Insect growth regulator
Carbaryl
Signal Word: Caution
Pesticide Class: Carbamate
Chlorpyrifos
Signal Word: Danger
Pesticide Class: Organophosphate
Clothianidin
Signal Word: Caution
Pesticide Class: Neonicotinoid
Cyfluthrin
Signal Word: Caution
Pesticide Class: Synthetic pyrethroid
Deltamethrin
Signal Word: Caution
Pesticide Class: Synthetic pyrethroid
Dinotefuran
Signal Word: Caution
Pesticide Class: Neonicotinoid
Dormant oil
Signal Word: Caution
Pesticide Class: Horticultural oil
Imidacloprid
Signal Word: Caution
Pesticide Class: Neonicotinoid
Imidacloprid+Bifenthrin
Signal Word: Caution
Pesticide Class: Neonicotinoid, Synthetic pyrethroid
Imidacloprid+Clothianidin
Signal Word: Caution
Pesticide Class: Neonicotinoid
Imidacloprid+Cyfluthrin
Signal Word: Caution
Pesticide Class: Neonicotinoid, Synthetic Pyrethroid
Insecticidal soap
Signal Word: Caution
Pesticide Class: Insecticidal soap
Kinoprene
Signal Word: Caution
Pesticide Class: Insect Growth Regulator
Lambda-Cyhalothrin
Signal Word: Caution
Pesticide Class: Synthetic pyrethroid
Permethrin
Signal Word: Caution
Pesticide Class: Synthetic pyrethroid
Pyrethrins
Signal Word: Caution
Pesticide Class: Botanical
Thiamethoxam
Signal Word: Caution
Pesticide Class: Neonicotinoid
Ultra-fine oil
Signal Word: Caution
Pesticide Class: Horticultural oil

Locations Affected

branches, fruit, leaves, stem, trunk

Plant Environment

greenhouse, outdoors

Scouting Season:

January - Early , January - Mid , January - Late , February - Early , February - Mid , February - Late , March - Early , March - Mid , March - Late , April - Early , April - Mid , April - Late , May - Early , May - Mid , May - Late , June - Early , June - Mid , June - Late , July - Early , July - Mid , July - Late , August - Early , August - Mid , August - Late , September - Early , September - Mid , September - Late , October - Early , October - Mid , October - Late , November - Early , November - Mid , November - Late , December - Early , December - Mid , December - Late

Plants Affected


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