Scales
Scale insects are the most common and troublesome insects
on camellias. They represent about 90% of the insect problem
on camellias. They usually go unnoticed until considerable damage
has been done and a large population has developed. Many of them
have several generations a year. They injure by sucking vital
juices from the plant
Tea Scale: This is the most common and probably
the most damaging insect pest of camellias. Tea scale infests
only the underside of a leaf. Male insects appear whitish while
the females are dark brown. Symptoms include yellow chlorotic
splotches on the upper leaf surface. A white, woolly-like, cottony-looking
mass secreted by the males may be seen on the under surface.
Camellia Scale: Like the tea scale, this
scale infests only the leaves of camellia. The female is light
to medium brown and oystershell-shaped about 1/10 inch long.
The male is similar but shorter.
Peony Scale: This scale is less common than
tea or camellia scale. However, when present it is a serious
pest. Infestations may kill branches and entire plants if not
controlled. Peony scale is found on the stems and branches of
camellias (and azaleas). They are hard to recognize as they camouflage
themselves well. The hard shell which covers their body is blended
to match the color of the stems. If the shell is removed, a white,
circular waxy spot is left on the stem.
Wax Scale - This scale is also found on the
stems and trunks of camellias and many other woody ornamentals.
The waxy covering is white or slightly pink, oval, and 1/4 inch
in diameter.
Control of Scale: Scale infestations are
more difficult to control when populations are heavy. Homeowners
should make spray applications when the first sign of scale is
seen. Oil emulsion sprays will give effective control if applied
properly. This is a contact insecticide. For it to be effective,
the plants must be thoroughly covered. Oil emulsion sprays should
be applied only during the spring and fall when the temperature
is 40 - 85° F. Spraying in the heat of the day may result
in burning the leaves. As a general rule, apply no more than
three times per year with at least 60 days in between sprays.
Oils are compatible with other insecticides.
Aphids or Plant Lice
These pests can become a problem during the peak growing time.
They are small insects that form colonies on the undersides of
leaves or along the stems of tender new growth. They are rarely
seen on mature, hardened tissue. They injure plants by sucking
their juices with a long beak. Aphids excrete honeydew, a sticky
substance which attracts sooty mold. Aphids are relatively easy
to kill although repeated sprays may be necessary. Soaps may
be used.
Mites
Mites are very small, sucking pets that may be found on either
the under or upper side of plant foliage. They are difficult
to see with the naked eye; a magnifying glass is helpful. Symptoms
include a dusty, gray appearance to the foliage. In heavy infestations
you may see webs covering infested areas. Heavy infestation may
also cause defoliation. A single spray of miticide in mid-May
usually prevents severe injury. A second spray applied in 10
- 14 days may be necessary to kill those mites which have hatched
from eggs. Mites are more severe in a hot, dry climate.
Camellia bud mites are small pests that occur under the scales
of vegetative and flower buds. flower buds with heavy infestations
show brown edges on the bud scales early. If left unchecked the
buds turn brown and drop before blooming. Thorough spray control
is essential to obtain good control of these mites.
ACS publishes Camellia Insects,
a leaflet of more information that is illustrated with color
photographs. Please
email the gift shop for ordering information for Camellia
Insects, item 4206/Insects. |
