Gloomy Scale Insect

Gloomy Scale Insect

Common Name: Armored scale; Gloomyscale

Scientific Name: Diaspididae; Melanaspis tenebricosus

Host Plants:

• Red Maple & Silver Maple preferred

• Elm

• Catalpa

• Hackberry

• Mulberry

• Sycamore

• Boxelder

Scouting and Possible Signs

Since they overwinter, you can scout for them at any time of the year.

• Carefully peel back the top coat of the scale to identify if it is still alive. Alive, they will be pink, orange or light brownish.

• Check for crawlers in May- June and take double sided tape on the bark and twigs to see if they are present.

   

Signs:

• Stunting and dieback of limbs

• Dark and white patches on bark

• Bark will have bumpy texture

• Thinning of leaf canopy

• Eventually can lead to death

Life Cycle and Biology

Nymphs are called crawlers and are less than 1mm and are yellowish-brown orange in color. They have tiny legs they use to crawl to a site on a tree, once establish a site, they will then start to produce the hard waxy covering. The covering will be brown to black with a pale ring around it

( Fig.1,2). The bodies are yellowish to brown in color, oval/sac-like in shape and it is both legless and wingless (Fig.1).

Males are much smaller in size, and as adults, they will have legs and wings ( Fig.2). Adult female covers are called tests (Fig. 3), and can be up to 2 mm wide with a central pale ring. The test is not attached to the body and can be peeled back to reveal the soft-bodied scale insect (Fig.3).

Spends winter as a female beneath protective coverings in bark, and in spring, resumes development by feeding via piercing-sucking mouthparts until she lays eggs underneath her tests. Eggs hatch sometime in late Juneand crawler activity may continue for 4 to 6 weeks. There has been very little research done on the crawler activity of this scale pest.

Management

• Horticultural oils

• Insecticidal soaps

• Insect growth regulators

• (IGRS)

• Systemic insecticide

For specific products under these management options or modes of action, contact your local cooperative extension office

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