Cryptomeria Scale (Aspidiotus cryptomeriae)
PDF version of Cryptomeria Scale - Facts at a Glance (with photos)
Where from: Japan
Host plants: Firs, dwarf Alberta spruce, other conifers
Symptoms: Prominent and severe mottling on foliage, premature needle drop
Important cultural practices: Field crews can transport Cryptomeria scale crawlers on their clothing and spread to other farms.
Scouting: Cryptomeria scale is not widespread in western NC. If you are near fields that have this scale, start scouting for it. Whenever in trees, look for mottling and determine the cause. Nymphs look like fried eggs. More mature scales look gray.
Life cycle:- How overwinters: Immature scales
- Number of generations per year: 2 generations
- Immature scales start to develop in spring. Males emerge and mate with females that produce as many as 40 eggs. These hatch in two weeks with crawlers emerging, typically in June. Second generation crawlers typically emerge in August.
Biological control: Twice stabbed lady beetle adult and larvae are primary predatorsControl considerations:
- Control with pesticides far easier than for elongate hemlock scale - HOWEVER - when scale numbers are high, they will stack on top of each other, making control more difficult.
- Good coverage is essential - target underneath of needles.
