Black Scale
[Saissetia oleae (Olivier), family Coccidae] is the major olive
pest in California, it is also a citrus pest in Texas, Florida and California.
Adult females are brown when young and become black when mature which are
2 to 5 mm long and nearly hemispherical, with a plainly visible elevated
ridge resembling the letter "H" on their back. Black scale eggs are 0.2
to 0.3 mm long and light colored when first laid, becoming pink after 2
or 3 days. A few days before hatching they become reddish orange color,
and nymphal eyespots become visible within the eggs. The first-instar nymphs,
called crawlers, are 0.3 to 0.4 mm long and pale yellow to light brown,
with dark eyes. The nymph's first molt is in 3 to 8 weeks. The second instar
nymphs are 1 to 1.3 mm, long and the "H" becomes distinct. The nymphs migrate
from the leaves to twigs at this stage. Chemical control is more effective
against these stages than the next stage which is the immature adult and
the adult stage.
The images are presented here in an intermediate size. By clicking on the image, the full size will be viewed for greatest detail. To get back to this menu, simply click on the BACK button in your browser.
Students may contact us at Department of Hort. Sci., TAMU for problems loading the files.
Return to: Main Menu
This site is maintained by Dr. Laurence Sistrunk, Dept. of Hort. Sci., Texas A&M University