Can Scale Affect a Cinnamon Tree?

Scale on Ceylon Cinnamon Tree

• Female pink wax scales (Ceroplastes rubens) and their larvae, or nymphs, feed on the Ceylon cinnamon tree's twigs, stems and upper leaf surfaces. The adult females cover themselves with a heavy layer of thick, pale-pink to pale red wax adorned with two distinctive white bands. This clearly visible shield protects the scales from dehydration, predators and insecticides. The 1/8- to 1/6-inch insects cling to the trees with sharp, beaklike mouths and drain nutrient-rich phloem sap. Each female lays between 300 and 1,100 eggs. Their pink-and-white nymphs crawl only a short distance, typically to tender new shoots, before attaching to feed.

Camphor Tree Scale

• Armored camphor scales (Pseudaonidia duplex) form protective shells of their shed skins, sealing them together with waxy secretions as they grow. Unlike pink wax scales' covering, these grayish-pink plates come away from the camphor scale's orange bodies when pulled. Like pink wax scales, these insects attach to the tree's branches and leaves to consume sap.

Damage

• Based strictly on the amount of damage its scales cause, Ceylon cinnamon makes a less desirable garden addition than camphor tree. The reason is honeydew, the sweet -- and very sticky -- waste with which soft pink wax scales drench the tree and any surrounding objects. Even when honeydew isn't immediately noticeable, the sooty mold fungi that cover it in greasy black layers certainly are. This mold doesn't feed on plant tissue, but it does weaken the trees by blocking photosynthesis and clogging its leaf stomata, the botanical version of nostrils. Camphor scales don't produce honeydew, but large numbers of either insect threaten their hosts with leaf loss, twig or branch dieback and even death.

Scale Management

• Pruning removes scale infestations limited to just a few branches. Trees growing in hot-summer climates also benefit from having their canopies thinned so the pests perish from heat exposure. Severely infested trees, however, require treatment with scale-smothering horticultural oil. A solution of 7 1/2 tablespoons -- or the manufacturer's specified amount -- of the oil per each gallon of water mixed in a pressurized sprayer kills scales in the crawler stage. It's effective when sprayed to saturate well-watered trees in late winter or early spring, when temperatures are below 90 degrees Fahrenheit. Follow-up applications every 30 days prevent reinfestation. Protective clothing, socks and shoes are advisable when using horticultural oil or any insecticide.