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What is on my plants?


Question
Spots
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Fluff on tree
Fluff on tree  
I was looking at my houseplants (havent been home a while I've been at college) and noticed that my blue elf aloe plant, and my other plant (cant think of the specific name) have these brown like specks all over them. Well to be specific mostly around the base even under the leaves, they havent gotten to the top of my blue elf. They look like shells a bit. There also seems to be shiny hardened liquid on the leaves. I think whatever was on my blue elf transfered to my other plant because they are touching, its not affecting my other plants(or my aloe vera) since they are not touching the afflicted Idk what to do.
Also on another one of my plants(tree I guess) there is white fluff pretty much all over the tree, the leaves the bark, I saw a little bit on my prayer plant as well.
How can I fix these problems?

Answer
Hi Azurle,
   The hard brown spots on the plant in the first picture are scale insects. The plant in the second picture has mealy bugs on it.
The hardened, shiny liquid you are finding on the leaves is called 'Honeydew'. Honeydew is a sweet sticky liquid, secreted by scale insects and other plant insects (Such as aphids) as they feed on plant sap.
As you are getting rid of the insects, be sure to get all of the honeydew cleaned off the whole plant, especially the leaves. A type of fungi, called 'sooty mold' commonly grows on the honeydew left on leaves. It is a black, powdery coating that sticks to the leaves and blocks the leaves from absorbing sunlight. It is also fairly ugly.

Unfortunately you are going to have to treat all of your plants for these insects, even if you have not seen any on the other plants. Eggs and immature crawlers can very easily be missed in the crevices, folds and creases on both the plant's leaves and stems that these insects like to hang out in.
Also mealy bugs have been known to deposit their eggs in places like the pot and the area immediately surrounding the pot (such as a window sill) as well as the plant itself.

Here is some information about scale and mealy bugs and your options in getting rid of them.

~ Mealybugs are soft-bodied, oval shaped, scale like insects with many legs. Mealybugs are covered by a sticky, white, cottony looking substance that extends out from it's body like short filaments. Mealybugs can be a problem to get rid of because the cottony substance often protects the insect from pesticides.

~ Scale insects are black, brown or tan, somewhat flat, oval shaped insects that are covered by a hard shell. Adult scales are stationary. Immature scales (called crawlers) emerge from eggs deposited under the adult females protective shell. Once crawlers establish a feeding site, they begin to secrete the hardened covering over their body. Adult Scale are a problem to control because their shell protects them from pesticides. Pesticides and soap sprays are most effective on crawlers.

There are several different types of commercial pesticides available. Always check the label of any pesticide you are thinking about using to make sure that the insect you want to get rid of is listed on the label. Also, as a general rule, always look for the word 'Houseplants' somewhere on the label of any product that you want to use on houseplants.

I can see from the pictures that there is quite a high population of these insects on your plants. With such a high population, I think that the best way to get rid of the scale and mealy bugs is by using a systemic insecticide. In cases of a very heavy infestation, a systemic is sometimes really the only effective means of control.

No matter which option works best for you, the first step in treating plants for insects is to spray the stems and leaves, especially the undersides, with a strong spray of water. This will wash off as many of the insects and eggs as possible.

A systemic insecticide is a insecticide that works by getting absorbed into the plant and distributed throughout all parts the plant. When an insect feeds on the plant it is poisoned. Systemic insecticides are especially good for severe infestations or reoccurring insect problems. There are two forms of systemic insecticides, one is a granule that gets mixed into the soil and is taken up into the plant by the roots. This form of systemic takes time to take effect, often 5-10 days. Personally, I do not think that granular systemics are really very effective.
The other, and best form is spray systemics. This form of systemic is sprayed onto the plant's leaves and is absorbed into the plant. This form works like a spray insecticide, killing insects on contact, then works as a systemic for lasting control.

*** A systemic insecticide will make any plant poisonous. Be sure to keep any and all plants treated with a systemic insecticide out of reach of children and animals. ***

If you do not want to use a systemic insecticide, then you can use either a commercial or homemade insecticidal soap spray. First wash off the plants. Then pick off as many scale and mealy bugs as you can with the cotton swab dipped in alcohol. You can also use tweezers to pick off the hard shells then wipe the area with a cotton ball soaked in alcohol.
Then mix distilled water, several drops of dishwashing liquid (Dawn works well for me) and about 3 tbsp of alcohol (90%) in a spray bottle. Spray the plants. To be effective, all plant parts and leaf surfaces, especially the underside, needs to be wetted thoroughly with the alcohol/soap spray. Repeat treatment every 5-7 days until there is no sign of a scale and mealy bug presence. It should probably take about 6 weeks.

The homemade insecticidal soap will also kill any other insects that may be lurking on your plants as well (such as spider mites, which are very hard to see, very common and often resistant to most chemical pesticides).
One of the biggest challenges with insect control is that once you have an insect presence on your houseplants it can very quickly become an out of control infestation. The best way to avoid a heavy infestation in the future is prevention, early detection and prompt adequate treatment. Check plants often for any sign of insect presence and if found, act quickly. Keep affected plants away from other plants to prevent the insects from spreading to other plants.

I hope this helps. If you have any questions or need additional information please don't hesitate to ask.
     Thanks
       Tracy

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