Leaf Mealy Bugs

Also known as Foliar Mealy Bugs

Description

Leaf Mealy Bugs are insects that typically measure 1/16 to 1/8 inch, though some may grow as large as 1/4 inch. Leaf Mealy Bugs are coated with a white, powdery, wax-like substance which makes them look like specks of cotton clinging to your African Violet. These specks of "cotton" will be visible on the undersides of leaves, in the leaf axils and in or near the crown of the plant. Leaf Mealy Bugs feed on the juices of African Violets. If untreated, they will eventually destroy your plant.

The name "Leaf Mealy Bug" is given to a category of several species. Some of the more common ones which might threaten African Violets are Citrus Mealy Bugs (Planococcus citri), Citrophilus Mealy Bugs (Pseudococcus calceolariae), Long-Tailed Mealy Bugs (Pseudococcus longispinus), Bakers or Grape Mealy Bugs (Pseudococcus maritimus) and Pseudococcus viburni (no common name).

Distinguishing Symptoms

• Leaves have white specks of "cotton" clinging to them.
• Stems have white specks of "cotton" clinging to them.

If your African Violet has these symptoms, it probably has Leaf Mealy Bugs. However, if what you see appears more weblike, your Violet may have Crown Rot or Spider Mites.

Other Symptoms

• Leaves have honeydew on them. Honeydew is a shiny, sticky substance left behind bycertain insects. (Note: Do not mistake the honeydew left by Aphids and other insects with the mucus trail left by Snails and Slugs.)
• Leaves have a black fungus on them. This is probably Sooty Mold, which finds a host in the honeydew left behind by Aphids and other insects. When Sooty Mold is present, the upperside of the leaves will be covered with tiny, dark speckles.
• Leaves wilt. They may appear translucent brown with a soft, jelly-like consistency.
• Leaves pale. They appear yellow or grayish in color.
• Plant growth is slow.
• Visible insects. Leaf Mealy Bugs are insects that typically measure 1/16 to 1/8 inch, though some may grow as large as 1/4 inch. Leaf Mealy Bugs are coated with a white, powdery, wax-like substance which makes them look like specks of cotton clinging to your African Violet. These specks of "cotton" will be visible on the undersides of leaves, in the leaf axils and in or near the crown of the plant.

Treatment

First, isolate any infested plants. This will help prevent any further spread of Mealy Bugs.

For light infestations, try rubbing the insects off with a cotton swab soaked in rubbing alcohol (70 percent isopropyl). Then, thoroughly rinse your African Violet with lukewarm water, and let any excess drain off. Repeat this procedure, each day, to remove any newly hatched Mealy Bugs.

For heavier infestations, you may need to apply Acephate (as directed on the label) or Malathion (1 teaspoon of Malathion 50 per 4 liters of lukewarm water). Repeat treatment, every four to five days, until the Mealy Bugs have been eradicated. (Note: Many household insect sprays, which contain Acephate, also contain a specific additive that may damage the foliage of African Violets. Therefore, if available, use a soluble powder, and mix your own spray.)

As an alternative to traditional chemical treatments, try spraying with Neem (Azadirachtin). Neem is a substance which has natural insecticidal properties, and according to currently available research, it is biodegradable and non-toxic. When sprayed on African Violets, it discourages Leaf Mealy Bugs by making the plant unpalatable. Though Neem does have some systemic effect in plants, spray it as you would other contact insecticides, being sure to cover the undersides of the leaves where Leaf Mealy Bugs tend to cluster.

Prevention

Always isolate new plants until you are sure they are not infested. Thereafter, keep a watchful eye on your African Violets. If at no other time, do a thorough examination of the leaves and stems every time you water. While there is no sure way to prevent Mealy Bugs, they are much easier to treat if caught early.

Important Note on the Use of Pesticides

Please note that almost all pesticides are formulated for specific uses and conditions. When applied incorrectly, pesticides can cause ill health or damage to plants. Therefore, when using any kind of pesticide or chemical treatment, always apply as indicated on the product label.

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