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Lepidosaphes yanagicola

Lepidosaphes yanagicola scale on Euonymus spp. Photo: John A. Davidson, Univ. Md, College Pk, Bugwood.
Scientific Name: 
Lepidosaphes yanagicola
Common Name: 
Scale On Euonymus alatus (Fire Bush Scale)
Growing Degree Days (GDD's): 
None available at this time.
Host Plant(s) Common Name (Scientific Name): 
Alder (Alnus spp.)
Elm (Ulmus spp.)
Linden (Tilia spp.)
Maple (Acer spp.)
Persimmon (Diospyros spp.)
Silk tree (Albizia spp.)
Willow (Salix spp.)
Winged euonymus (Euonymus alatus)
Insect Description: 

Lepidosaphes yanagicola is sometimes referred to as the fire bush scale or the yanagicola oystershell scale. This is a different species than the euonymus scale (Unaspis euonymi) which is also found on Euonymus spp. The fire bush scale is an armored scale pest of euonymus as well as other deciduous hosts. It will not be found on evergreen euonymus. On winged euonymus, this armored scale will be found most frequently on twigs between the bark ridges that form the "wings". In heavy infestations, however, the scales may be found near leaf midveins. Fertilized adult females of this species overwinter (approx. 2 mm long and oystershell shaped, brown; bodies beneath the test or armored covering are white). The female test is straight unless the population of scales is large and individuals become crowded. Males have shorter tests and are orange-brown in color. Egg laying at sites in Pennsylvania has been recorded in mid-June and continues for a month. Eggs are white. Immature fire bush scales (crawlers, also white in color) will mature into adults and mate prior to the arrival of frost. All life stages may be observed from late July into August. In Ohio, crawlers may be present by late-June. In Maryland, crawlers are also reported in June. Historically, in Massachusetts, the crawler stage has been reported by mid-to-late July (Robert Childs, personal communication). A single generation has been observed per year. The fire bush scale is reported from: Georgia, Indiana, Maryland, Massachusetts, Missouri, New Jersey, Ohio, Oklahoma, Pennsylvania, Rhode Island, Tennessee, Virginia, and West Virginia. The fire bush scale is also known from China, Japan, Russia, and South Korea. On Euonymus spp. hosts, the fire bush scale may be confused for L. gloverii (Glover scale), however that species is more commonly known to Citrus spp. A scale taxonomist would be able to differentiate between the species using slide-mounted characteristics viewed under a microscope (Miller and Davidson, 2005).

Damage to Host: 

Heavy infestations of this armored scale can cause premature leaf drop, twig dieback, and susceptibility to winter injury. Scientists classify this insect as an occasional or significant pest, depending upon location. Heavy infestations on Euonymus spp. that cause premature leaf drop and dieback have been observed in Maryland. Heavy infestations and damage by the fire bush scale have also been reported from Ohio nurseries. On winged euonymus, heavy infestations have caused premature leaf drop and twig dieback in nurseries in the northeastern US; but in Pennsylvania, on the same host and in heavy populations, damage is rarely seen. 


Inspect plants closely, especially the stems and between the winged, bark ridges. Populations may not be noticed until leaves are off-color or premature leaf drop occurs. Visually monitoring for this armored scale should be done in the fall and dormant season, so that heavily infested stems can be managed by pruning before egg hatch.  

Cultural Management: 

If found only on a few branches, the fire bush scale may be destroyed by pruning out and removing the heavily infested branches. If possible, do so before crawler emergence. 

Natural Enemies & Biological Control: 

Two species of tiny, parasitic wasps are noted as natural enemies of the fire bush scale. These include Alaptus auranti and Alaptus pallidicornis (Herting and Simmonds, 1972).

Chemical Management: 

Abamectin (NL)

Acephate (NL)

Acetamprid (L)

Azadirachtin (NL)

Buprofezin (NL)

Carbaryl (L)

Chlorpyrifos (N)

Clothianidin (NL)

Cyantraniliprole (NL)

Cyfluthrin (NL)

Dinotefuran (NL)

Gamma-cyhalothrin (L)

Horticultural oil (L)

Imidacloprid (L)

Insecticidal soap (NL)

Lambda-cyhalothrin (L)

Neem oil (NL)

Pyrethrin + sulfur (NL)

Pyriproxyfen (L)

Spinetoram + sulfoxaflor (N)


Active ingredients that may be applied systemically include: abamectin (injection), acephate (injection), acetamprid (injection), azadirachtin (injection, soil drench), clothianidin (soil drench), cyantraniliprole (soil drench, soil injection), dinotefuran (soil drench), imidacloprid (soil drench), and neem oil (soil drench).

Make insecticide applications after bloom to protect pollinators. Applications at times of the day and temperatures when pollinators are less likely to be active can also reduce the risk of impacting their populations.

Note: Beginning July 1, 2022, neonicotinoid insecticides are classified as state restricted use for use on tree and shrub insect pests in Massachusetts. For more information, visit the MA Department of Agricultural Resources Pesticide Program.

Read and follow all label instructions for safety and proper use. If this guide contradicts language on the label, follow the most up-to-date instructions on the product label. Always confirm that the site you wish to treat and the pest you wish to manage are on the label before using any pesticide. Read the full disclaimer. Active ingredients labeled "L" indicate some products containing the active ingredient are labeled for landscape uses on trees or shrubs. Active ingredients labeled "N" indicate some products containing the active ingredient are labeled for use in nurseries. Always confirm allowable uses on product labels. This active ingredient list is based on what was registered for use in Massachusetts at the time of publication. This information changes rapidly and may not be up to date. If you are viewing this information from another state, check with your local Extension Service and State Pesticide Program for local uses and regulations. Active ingredient lists were last updated: January 2024. To check current product registrations in Massachusetts, please visit: .