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Carulaspis minima

Minute cypress scale. Photo: D.K.B. Cheung, University of Maryland Extension.
Scientific Name: 
Carulaspis minima
Common Name: 
Minute Cypress Scale
Growing Degree Days (GDD's): 
None available at this time.
Host Plant(s) Common Name (Scientific Name): 
Arborvitae (Thuja spp.)
Cypress (Cupressus spp.)
False cypress (Chamaecyparis spp.)
Japanese cedar (Cryptomeria spp.)
Juniper (Juniperus spp.)
Leyland cypress (Cupressus x leylandii)
Plum yew (Cephalotaxus spp.)
Spruce (Picea spp.) 
Cedrus spp.
Sequoia spp.
Insect Description: 

Female scale covers slightly convex, circular to oval, white, and are approximately 1.5 mm in diameter and have a darker yellow center. The male scales are elongated, oval, with 1-3 ridges, and have more white coloration than the females. The minute cypress scale overwinters as a mature female found on host plant leaves or needles. By May in the Northeast, females will begin to lay up to 40 reddish-yellow eggs which will hatch approximately 2 weeks later. Yellowish crawlers (the mobile, immature stage) will move and find a new location to settle and begin to feed on the host plant. Like many scale or adelgid crawlers, they are capable of dispersing via the wind. Once settled in a suitable location on the host plant, they begin to feed. Female crawlers will go through 3 instars, and the males will go through 5. Males will eventually mature into tiny, winged individuals that fly to mate with the adult females. This happens in late summer or early fall. In the cooler parts of the insect's range, a single generation occurs per year. This might be the case in most locations, however some sources state that two generations per year are possible in California. A closely related species, Carulaspis juniperi, also known as the juniper scale, looks identical to the minute cypress scale in the field and is found on many of the same host plants. It is possible that the two could easily be confused for one another. (In fact, for many years scientists treated them as a single species.) The minute cypress scale may be slightly smaller than the juniper scale. This species may be more prevalent in the southern United States as it prefers a warmer climate, however specimens have been collected in the past from Massachusetts (Johnson and Lyon, 1991; Miller and Davidson, 2005).

Damage to Host: 

A first indication of infestation by this scale may be that the host plant looks dull in or off color. The minute cypress scale is a serious pest of juniper. Damage to the host plant can include branch dieback, leaf drop, and when the population is high enough or other stressors are involved, even host plant death. Trees weakened by this scale may also be susceptible to other pest invasion. This insect may be a significant pest in ornamental nursery production. Because this is an armored scale insect, no honeydew (or subsequent sooty mold) is produced.


Visually scout for host plant species that look off color or are exhibiting other symptoms of armored scale infestation. This can be done any time of the year. If found in a previous season, this information is helpful for possibly planning dormant oil applications the following spring. Monitor for female egg laying in May and crawler activity possibly from mid to late-May.

Cultural Management: 

If possible without disfiguring the host plant, prune out and destroy heavily infested branches. 

Natural Enemies & Biological Control: 

Natural enemies of the minute cypress scale are abundant. At least 22 different genera in 11 families have been reported. This includes but is not limited to certain species of mites (Acaridae; Tyrophagus), parasitoid wasps (Aphelinidae; Aphytis and Encarsia), (Encyrtidae; Habrolepis rouxi), and various different species of ladybeetles (Coccinellidae; Chilocorus, Pharoscymnus, and Telsimia), among many others. ScaleNet provides a very thorough and comprehensive list for this species.

Chemical Management: 

Abamectin (NL)

Acephate (NL)

Acetamiprid (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)


When used in a nursery setting, chlorpyrifos is for quarantine use only.

Active ingredients that may be applied systemically include: abamectin (injection), acephate (injection), acetamiprid (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: .