Insects - Scale
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  (April) I have a problem with my 18 year old camellia tree. Usually it has red blossoms in the spring. This year it looks sick and the few blossoms are far from their normal beauty. There is a white covering on the leaves which is probably some sort of disease. I would appreciate any suggestion you have for treating this problem.

  I do not think you have a disease but an insect problem. I have seen an abundance of scale this year on everything from hollies to camellias. Scale insects can vary in size from a half inch to the size of a pinhead. On camellias, the most common scale is called tea scale. These insects attach themselves to the leaves and suck the sap out. As they multiply, it can severely impact the plant. Each female deposits from 10 to 15 eggs under the scale shell. They hatch in 7 to 21 days, depending on the weather. The flat, yellow crawlers migrate to the newer growth on the plant and, in 2 or 3 days, attach themselves. At first they secrete thin, white coverings, but shortly afterward they produce great quantities of white threads. As the population builds up, the undersides of the leaves may be covered with this cottony secretion. From 41 to 65 days after hatching, female scales begin to lay eggs. The life cycle is usually completed in 60 to 70 days. The hatching of tea scale nymphs occurs throughout the year, although it is less frequent in cold than in warm weather. If left unchecked, they can build up quite quickly. Use a systemic insecticide such as Di-syston, Bayer Advanced Tree and Shrub insecticide, or try spraying with Orthene. Contact sprays are difficult to control these insects since we have such a heavy network of leaves, and the insects do most of their feeding on the underside of leaves.

  (May) We've discovered this spring that the older leaves on our hollies are covered on the top with a black substance that can be scraped off. What can we do to correct this and what causes it?

  Take a look at the back side of the leaves and along the stems. I bet they are covered in tiny white specks. This is tea scale, and it has been pretty bad on many hollies this year. The scale insects suck the sap out of the foliage, and give off a sticky honeydew. Wherever the honeydew fall, black sooty mold will collect. You need to get a handle on the scale insects, because if left unchecked, they can damage and eventually kill the holly. Bayer Advanced Tree and Shrub insecticide, Di-syston and Orthene are all products that can give you control. You may need more frequent applications of some of these products, so read and follow label directions.

  (May) I have a 10 to 11 year old red dogwood that bloomed well three years ago, but since then, it hasn't produced more than 3 or 4 blooms. I think I have a scale problem. There are small black or brown hard shelled bug attached mostly in crotches. I sprayed with oil spray in January, dumped a ton of dysyston over roots for last 15 months, sprayed with dormant oil spray mixed with Malathion plus as directed on label 10 days ago. I pick bunches of new insects every afternoon since. I have a second red dogwood 40 yards away that I don't see any bugs on & it is younger & and is always covered with blooms. Might this be something other than scale insects? Any other suggestions?

  It could be scale, but do keep in mind that once the scale dies, it stays attached. You may be getting a bit extreme in the insecticide applications. Toxicity from chemicals can also hinder growth, and thus blooms. If you don't see new signs of scale infestation, hopefully you have it cured. Shade can also be a limiting factor in blooming. To make sure you have scale, take a sample or photo to your county extension office.

  (October) I bought two camellia plants, planted them as directed, approximately six feet apart. One is dark green, setting blooms, and thriving. The other is losing leaves, turning yellow, and (here's the kicker) has small white blobs on the stems and leaves. These blobs feel a bit like popped pop corn but definitely have something living inside them. When I squished one, it made a crunch sound and a red liquid oozed out. Really quite "Alien" if you ask me. So that's why I'm asking you. What do you think?

  It sounds like scale insects to me. The most common scale insect we have on camellias is the tea scale -- but they are small and look almost like grains of salt coating the stems and leaves. Since yours are larger, I would guess probably oyster scale, which has a white waxy feel to it, and can grow quite large. Mealy bugs are soft bodied scales that have a white cottony growth covering them. Scale insects suck the sap out of the plants and with a heavy enough build up, can cause damage, even death over time. Systemic insecticides such as Di-syston and Bayer Advanced Tree and Shrub insecticide are quite effective but take time. Dormant oils can be used to smother out the insects, but thorough applications are needed on all parts of the plant -- upper and lower surfaces of leaves, stems, etc. Do keep in mind that once the insects have died, they will still be present on the leaves, but you should see new growth that is healthy and the plants should appear more thrifty. Also, if the plants were newly purchased, you might also contact the nursery or garden center and see about an exchange.

  (October) I have a golden Euonymus bush that is dying. Close to half the leaves have fallen off and the exposed branches and many leaves are spotted. Is there anything I can do to save it? 

  I bet if you look closely, the plant is probably inundated with scale insects. Euonymus plants have their very own scale insect. I often describe it as a salt-and-pepper type coating on the stems, leaves, etc. Heavy infestations will make the plants decline. If it is heavily damaged, cut off the main damage and spray with a dormant oil. Saturate the plant and remove the old mulch. Keep some spray handy, since Euonymus plants are commonly plagued with scale.

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