Green Industry - A Knowledge Portal for Commercial Horticulture in Wisconsin (sponsored by University of Wisconsin-Extension)
Diagnostics - Problem Details
Armored scale - Diaspididae family
Description
Armored scales are oval, somewhat elongate (think oyster shell), small (1/20-1/8") insects that secrete a hard, waxy cover. During the adult stage, no body parts are visible except the cover. Eggs are laid under the cover and hatch into crawlers, which can move around and are susceptible to sprays and oils.
Damage
Armored scales do not produce honeydew. They may kill plant tissue where they feed, producing twig dieback, yellowed leaves and distorted foliage. With heavy infestation, chlorosis may be followed by browning and defoliation.
Cultural Controls
Inspect leaf undersides and stems frequently for the presence of scales. Remove and destroy heavily infested plants. Dislodge crawlers with water sprays. Inspect all new plant material on arrival.
Remarks
Use ultra-fine oils after new plant growth emerges. Armored scales are susceptible to oils during the crawler stage before their protective shells harden. Apply lime sulfur during the dormant season only.
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 - 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 - Lime sulfer
- Signal Word: Danger
Pesticide Class: Inorganic - Malathion
- Signal Word: Warning
Pesticide Class: Organophosphate - 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
Plant Environment
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