The Sago Palm (Cycas revoluta) is part of the Cycad family. The Sagos are slow growers taking years to mature.
Cycads are tough, primitive, and have been around since the Triassic and Jurassic era. They may be tough but, it is still essential to protect your cycad plants from the Sago Palm scale.
Large specimens of Sago Palms have thick trunks about two feet in diameter and can grow up to ten feet high.
The dark green, spiny leaves can grow about four feet long. Cycad palm trees can have multiple trunk heads, each sprouting multiple sets of leaves.
What Are Sago Palm Scale Pests?
When hearing the word “scale,” someone might think of scales on reptiles. It is not that far off for comparison. Cycad scales grow under a wax covering resembling reptilian scales.
There are many species of plant scale insects. The most common scale insects that infect the Sago Palm are Cycad aulacaspis yasumatsui, or Asian cycad scale, and Pseudaulacaspis cockerelli, or false oleander scale.
The Asian cycad scale feeds on the bottom of fronds. The false oleander scale feeds on the tops of fronds.
These insects are flat and oval and are commonly tan, white, or brown. Scale insects are tiny, as tiny as a pinhead. There are two categories of scales, soft and armored.
Soft scales look like soft, white, powdery dots. Armored scales appear as hard, dark dots. Cycad aulacaspis scale over time will cover the entire plant stems, trunks, and foliage.
The eggs hatch under these “dots” and become larva or crawlers.
According to Diseases & Pests of Ornamental Plants 10 scale insect species attack Cycas including: Black, California red, chaff, Florida red, green shield, hemispherical, oleander, pineapple, purple and soft.
Sago Problems – Why Is My Sago Palm Yellowing?
What Damage Does Scale Cause?
Scale insects, specifically the crawlers, suck sap from the Sago Palm. As the crawlers feed on the sap of Cycas revoluta, it excretes a sticky substance called honeydew.
This honeydew attracts ants, flies, and other insects.
Honeydew also traps fungus spores. The honeydew leads to sooty mold, which looks like black soot and prevents light from getting through to the leaves.
While scale insect pests are incredibly tiny, the “scales” are easy to see.
Check for white or black dots, or scales, on the tops and bottoms of your Sago Palm. On heavily infested Sago Palms, the leaves will look white.
Check to see if the scales are alive by scraping them. If the scales are dead, they will be dry and powdery. If the scales are moist and squishy, they are active.
How To Control Sago Palm White Scale
Scale can devastate Sago Palms. Luckily, getting rid of the scale insects is easy to do naturally or with chemicals. Always read the label directions before applying any chemical.
Natural Treatments and Methods To Get Rid of Scale
If your Sago Palm is suffering from scale, getting rid of them naturally takes patience.
The first natural method for ridding scale is to prune your Sago Palm. Heavily infested fronds can be pruned, placed in a sealed bag, and disposed of away from plants. Prune any sick-looking fronds too.
Related: Planting and Growing Sago Palm Seed
If the scale found is not too much, you can scrape it off with a fingernail, credit card, or dull object. Note that you might need other methods to prevent the scale infestation from returning.
Use a cotton ball soaked in isopropyl alcohol to dab the pests. If you can, scrape the scale off with the cotton ball.
This will disintegrate the scale and any honeydew leftover. Do this method every two to three days to ensure that the scale is gone permanently.
Another method is to use neem pesticide oil. Spray your Sago Palm leaves, top and bottom, and all parts of the plant with the neem oil. Mix water and neem that contains azadirachtin, which slowly kills scales and leaves a protective coat on the Sago Palm.
Neem can also be used as a drench. Details On: How To Mix Neem Oil As A Soil Drench
NOTE: It is recommended when spraying sago palms to spray in the early morning when the temperatures are cooler.
Other options include applying a horticultural oil spray, ultra-fine oil or SunSpray oil)
Try an insecticidal soap on your Sago Palm. These soaps work by clogging the respiratory spores on the scale insects, causing them to suffocate.
Most insecticide soaps are organic and won’t damage the Sago Palm. Be sure to wash the soap off between applications to not block the pores on the Sago Palm.
Use insecticidal soap every three days to ensure the scale is gone.
Be sure to research insecticidal soap to make sure it contains only organic ingredients and won’t harm your plant, animals, or humans.
Details on: How To Make Homemade Insecticidal Soap
For a light, infestation introduce natural predators (biological control) such as ladybugs and parasitic wasps into the garden.
Chemical Methods to Get Rid of Scale
Get rid of scales using systemic insecticides. A systemic plant insecticide is absorbed through the trunk or root and translocated to other plant parts. Be sure to follow the instructions for proper use.
Horticultural oil is also a suitable chemical method for getting rid of the scale.
Application of horticultural sprays can kill scale at any life stage and work by blocking respiratory spores on the scale.
NOTE: Use these plant scale controls on the King Sago – Cycas circinalis.