This publication explains how to control Florida wax scales, which have begun attacking hollies in Texas. 6 pp., 4 photo

Drees, Bastiaan M.

Reinert, James

Williams, Michael  L.

Texas A&M University

Florida Wax Scales: 
Control Measures in Texas for Hollies 
Bastiaan M. Drees, James A. Reinert and Michael L. Williams*
* Professor, Extension Entomologist and Regents Fellow, The 
Texas A&M University System; Professor of Entomology, Faculty 
and Regents Fellow, Texas Agricultural Experiment Station, 
The Texas A&M University System; Professor of Entomology, 
Department of Entomology/Plant Pathology, Auburn University
Hollies have historically been good choices as landscape plant species in Texas and are well adapted to the state’s environmental condi-
tions. However, in recent years a new pest has begun 
attacking the hollies (Ilex spp.) here.
Landscape hedges of hollies throughout the east-
ern half of Texas and the southeastern United States 
are increasingly becoming infested with the Florida 
wax scale, Ceroplastes fl oridensis Comstock (Homop-
tera: Coccidae) (Fig. 1).  When plants are heav-
ily infested with wax scale, the leaves, or foliage, 
become blackened with coatings of a fungus called 
sooty mold. 
Wax scales injure plants by removing large 
amounts of plant sap. Severe infestations may discol-
or the leaves, cause shoots or branches to die back 
and occasionally kill the entire plant. Wax scales also 
produce honeydew, which serves as a medium for 
the growth of sooty mold and attracts insects such as 
bees, wasps, hornets and ants (Hymenoptera). 
The sooty mold colonizes (or grows) on the hon-
eydew, causing the infested plant parts to turn black 
and unsightly. This mold also attracts some species 
of bark lice (Psocidae). 
When the plants are infested heavily, it is diffi cult 
to control these insects, in part because you must 
time the spraying properly as well as coat the leaves 
thoroughly with insecticide. Even after the insects 
are killed, many of the scales and sooty mold will 
remain on the plants and continue to disfi gure them.
Identifi cation
To keep from wasting time, effort and money on 
control efforts that work incompletely or not at all, 
it is important that you fi rst identify the problem 
correctly. Many species of scale insect infest orna-
mental landscape plants. However, none have the 
shape and size of this group of soft-scale insects: 
wax scales are globe-shaped and coated with a heavy 
layer of wet-looking white, beige, pinkish white or 
grayish wax. 
From the top view, the insect appears rectangu-
lar, oval or lobed at the base. Under the wax cap, 
the body of the scale is reddish. The adult female 
Florida wax scale grows to about 3 millimetes (1⁄8 
inch) in diameter.  
L-5479
12/06
Figure 1. Holly leaf infested with Florida wax scale.
Many other species of wax scales occur in the 
state, including the larger barnacle scale, C. cirripedi-
formis Comstock, which grows to almost 1/4 inch in 
diameter. 
Biology
Because timing is vital in controlling Florida wax 
scale, you need to know about the life cycle of this 
insect. 
The eggs (Fig. 2) of this species are oval and red-
dish orange. They fi ll the cavity under the bodies of 
dead or mature adult female scales. 
From the eggs hatch Florida wax scale nymphs. 
The nymphs feed and develop through three stages, 
which are known as the fi rst, second and third 
instars.
 First-instar nymphs (Fig. 3) hatch from eggs over 
2 to 3 weeks. Then these nymphs, called crawlers, 
move to and settle on the leaves, twigs and stems 
of the host, spreading the infestation. When a new 
fl ush of growth occurs on a host plant, the crawlers 
will often migrate to the new growth at the top of 
the plant. 
Scales often line up along the veins on top of the 
leaf (Fig. 4). Florida wax scale nymphs can move 
from one place on the plant to another. 
After settling, the nymphs insert their thread-like 
mouthparts into the plant and begin to secrete wax 
in tufts around their bodies, which gives them a star-
like appearance. 
After the third instar, the scales become adults, 
produce eggs, and die. If you remove an individual 
adult female scale from a leaf at certain times of 
the year, hundreds of eggs will pour out of its body 
cavity. 
In Texas, the Florida wax scale has two fairly 
distinct generations per year: The eggs hatch in late 
April through May and again in late July through 
August. However, some eggs can hatch during other 
months. 
Florida wax scales overwinter (spend the winter) 
as newly mature females. Male forms have not been 
observed in this species. 
Other host plants
Florida wax scales infest a wide range of host 
plants, including shrubs, trees and several herba-
ceous plants. In Florida, it has been found on many 
species of holly, elm, crape myrtle, oak, loblolly 
pine, deodar cedar, citrus and other hardwoods and 
softwoods. In Texas, wax scale infestations have 
been observed on hollies as well as elephant ear, 
Figure 2. Eggs from beneath an adult female wax scale.
Figure 3. Settled crawlers and (inset) active crawlers.
Figure 4. Adults.
2
golden euonymous, honeysuckle, pomegranate, 
winged elm and Virginia creeper. 
Florida wax scales are easily spotted on holly 
because most of them are found on top of the leaves. 
This location makes the scales easier to reach with 
foliar insecticide sprays. It also makes them vulner-
able to heavy rain and other environmental factors 
that reduce their ability to survive. 
However, some of the scales infest twigs, branch-
es and the undersides of leaves, where they are 
more protected.  
Distribution    
Florida wax scale is widely distributed from 
Maryland to Florida, including the Caribbean archi-
pelago, and from Missouri to California. In recent 
years, infestations in the eastern half of Texas have 
become particularly noticeable. 
Management
In Texas, you can control Florida wax scale 
through cultural and chemical methods. 
Cultural control: To eliminate the need for 
repeated insecticide treatments on heavily infested 
hollies, consider replacing them (and other host 
plants) with species that are not attacked by Florida 
wax scale. Alternative shrubs include junipers (ex-
cept ‘Blue Point’ juniper), ligustrum, privet, box-
wood, pittosporum, bottle brush, sea grapes, olean-
der and wax myrtle (regular and dwarf). 
Of course, these landscape ornamental plants may 
have other limitations. If you decide to plant hol-
lies, inspect the plants thoroughly to avoid buying 
infested plants. When planting them, choose and 
prepare appropriate planting sites, then water and 
fertilize the hollies properly. 
Check the plants regularly for early signs of an in-
festation of wax scale or other pests. If you decide to 
preserve the plants once they have become infested, 
fi rst prune away and discard all the heavily infested 
foliage. This will remove some of the pests and open 
the canopy, which will allow you to spray the leaves 
more thoroughly and get better coverage. 
Chemical control: The goal of using insecticides 
should be to prevent new plant growth from be-
coming infested by crawlers. The treatment options 
include:
• Systemic insecticides (those that are absorbed 
and circulated by a plant so as to kill the pests 
that feed on it) applied to the soil, and/or 
• Foliar sprays
Choose a product that has a label listing scale 
insects or soft scale on ornamental landscape plants. 
Specifi c chemical application guidelines are detailed 
on the following pages. 
Similar treatments on other landscape plants may 
help control other pests such as azalea lace bugs and 
crape myrtle aphids, but check the timing of ap-
plications because they vary for different pests and 
plants.
Systemic soil treatments: Because systemic 
insecticides generally do not eliminate all the scales 
from the branches or twigs, you may need to apply 
them more than once to eliminate the population.   
If you choose a soil-applied systemic insecticide, 
such as one containing imidacloprid (for example, 
Merit®, Bayer Advanced™ Tree & Shrub Insect Con-
trol), apply it before egg hatch to allow the active 
ingredient to be moved from the soil through the 
roots and into the leaf tissue. 
The scales that are attached to the branches or 
twigs may be unaffected by this systemic soil treat-
ment. Those killed by the insecticide may persist for 
a period of time before falling off. Carefully follow 
the directions on the product label.
Foliar sprays: Leaf treatments are best applied 
after the crawlers hatch from the eggs and begin to 
settle on new foliage. Beginning in late April and 
again in mid-August, examine the leaves on the 
infested plants every 1 or 2 weeks for newly settled 
nymphs. They will appear small, white and starlike 
as they begin secreting their wax coating. 
You may need to spray the leaves several times in 
7- to 10-day intervals or as directed on the product’s 
label. This spray schedule will protect the new foli-
age through the period of egg hatch, particularly 
if it is the type of insecticide that offers little or no 
residual (long-lasting) activity, such as insecticidal 
soap or horticultural oil. 
For a longer period of control, use a contact 
systemic foliar spray such as products containing 
acephate (example: Orthene® Tree, Turf and Orna-
mental Spray). This type of pesticide kills insects 
on contact, but it is absorbed into the leaf tissue, 
providing a longer period of control.
Biological control: In some parts of the United 
States, three parasitic wasp species (Coccophagus ly-
cimnia, Scutellista cynea and Metaphycus eruptor) have 
been used to biologically control Florida wax scale. 
However, no natural enemies (pathogens, parasites, 
predators) of wax scale have been observed in Texas. 
3
Chemical Application Guidelines
Applying a systemic insecticide to the soil
1. Assemble the proper equipment and sup-
plies—product, applicator and protective 
clothing. Before proceeding, be sure that your 
protective clothing and the application equip-
ment are clean and in good repair after the 
previous use. After making an application, 
clean and store the equipment and protective 
clothing properly.
2.  Mark the designated equipment properly. 
If you are using a sprinkler can or other equip-
ment to apply a pesticide, write a warning such 
as Insecticide Use Only on the container. Do not 
use this equipment for other purposes. Do not 
use herbicides in the same equipment used for 
insecticides or miticides.
3.  Read the product label thoroughly. The la-
bel will specify the safety equipment required, 
such as gloves or goggles, long-sleeved shirts, 
pants and shoes. Review this section to deter-
mine the application rate and the concentration 
of material to be applied. 
 Also check the re-entry interval (the period 
immediately after the application of a pesticide 
to an area when unprotected people should not 
enter it), if any. 
4. Measure the height of the plant. When 
using Bayer Advanced™ Tree & Shrub Insect 
Control containing imidacloprid, the use rate 
(gallons of diluted solution to pour around the 
root zone) varies according to plant height. 
Other products may contain ingredients and 
have different rates and directions for use.
 Prune the plant to eliminate heavily infested 
leaves to reduce the plant height, which will 
allow the new growth to be protected by the 
insecticide.
5.  Wear proper personal protection. Possibly 
the most dangerous step in using a pesticide 
is when you are mixing water with the con-
centrated insecticide from the container. Wear 
gloves and other clothing described on the 
product label before opening the container and 
mixing the concentrate. 
6.  Shake the container. When stored for long 
periods, some pesticide formulations settle and 
separate. Always shake the container to agitate 
the contents before opening it.
7.  Partially fi ll the applicator tank or con-
tainer with water. This step will help the 
concentrate go into solution and prevent the 
concentrated insecticide from coating the sides 
of the applicator container. Adding more water 
later will also help stir this solution.
 8.  Add the proper amount of insecticide. 
The product label will list the amount of the 
pesticide to mix with a certain amount of 
water. To control soft scales (including Flor-
ida wax scales) on holly shrubs using Bayer 
Advanced™ Tree & Shrub Insect Control, 
apply 3 fl uid ounces per foot of plant height 
to the root zone or the soil under the shrub. 
Use a well-marked measuring cup (mark it 
Poison).
 9.  Pour the concentrate into the applica-
tion container, and rinse the measur-
ing cup or spoon. Using water to fi ll the 
applicator, rinse the measuring cup or spoon 
three times to help remove the concentrated 
insecticide and mix it into solution.
 10.  Apply the diluted solution to the root 
zone. Sprinkle the insecticide solution on 
the soil under the canopy of the shrub and 
then water it in as directed. Systemic insec-
ticides such as imidacloprid are moved from 
the roots in the soil to the leaves. Do not 
apply them to very wet or saturated soils. 
The solution must penetrate into the soil and 
stay in place so the roots can pick up the ac-
tive ingredient. 
Timing: For Florida wax scale, you need to apply 
the insecticide to the soil several weeks before the 
eggs hatch. In Texas, this species has two distinct 
generations: one in late April and the second in late 
August. 
Because the scales on the branches and twigs may 
be unaffected by systemic insecticides applied as a 
soil drench, you may also need to treat the leaves 
with a foliar spray to eliminate the infestation. In 
late May and late September, check for new young 
scales on the leaves to determine whether the treat-
ment was successful.
Applying a foliar spray
1. Carefully read the label directions on the 
container or the labeling leafl et supplied 
with the product’s container. The directions 
provide information about personal protective 
clothing, timing(s) for making application(s), 
equipment required and the rate of product 
to apply. Orthene® Tree, Turf and Ornamental 
Spray is a soluble powder formulation, one 
of several formulations containing the active 
ingredient acephate (75 percent concentrate). 
2. Add some water to the applicator con-
tainer. Make sure the applicator works, as 
the nozzle may be clogged or the seals in older 
compression sprayers can prevent pressure 
from building up in the tank. Also, use this wa-
ter to help agitate the concentrate insecticide so 
it can mix into a dilute solution. 
4
53. Measure out the proper amount of con-
centrate insecticide. For scale insect control, 
Orthene® Tree, Turf and Ornamental spray is 
applied at a rate of 1 teaspoon per gallon. Wear 
proper application clothing and use a desig-
nated measuring spoon (mark it Poison).
4. Fill the applicator with remaining amount 
of water. Add water after adding the insec-
ticide powder or concentrate to help agitate 
the solution and mix the insecticide to make a 
dilute solution. Use larger equipment for larger 
tasks.
5, Wear goggles, gloves, long pants and a 
long-sleeved shirt. As directed on the prod-
uct label, and particularly when using fi ne, 
droplet sprays and needing to crawl through 
shrubbery, take all precautions to avoid getting 
the insecticide in your eyes or on your skin or 
clothing.
6. Pump up the sprayer. Follow the manufac-
turer’s recommendations to pressurize the 
sprayer tank. Agitate the insecticide solution 
again before spraying. 
7. Start spraying the most inaccessible areas 
fi rst, and back away from treated foliage 
areas. Avoid brushing up against just-sprayed 
foliage. Spray the undersides of the lowest 
leaves fi rst.
8. Treat the upper leaf surfaces last. The Flor-
ida wax scale settles mainly on the upper leaf 
surfaces. However, some egg-laying females 
can be found on branches, twigs and the un-
derside of leaves. You need to cover the leaves 
thoroughly to eliminate the whole population. 
 Use all of the mixed-spray solution. Do not 
leave unused solution in the sprayer because 
the insecticide will decompose and the liquid 
will corrode and ruin the applicator.
Orthene® or acephate is a contact and systemic 
insecticide that is applied to leaves, absorbed into 
leaf tissues and moved by the plant to new growth. 
Scales that come into contact with the spray will be 
killed, and the foliage containing acephate will kill 
young scales that settle on the leaves and begin to 
feed on the plant sap. 
Timing: In Texas, the Florida wax scale eggs 
hatch primarily twice per year, although some eggs 
can hatch at any time. Egg hatch occurs over sev-
eral weeks during each generation (late April and 
late August). Foliar sprays are most effective when 
applied during the crawler stages of this scale insect 
fi rst settle on the foliage to start feeding. 
The Orthene® label recommends applying this 
foliar spray at 2-week intervals through the egg 
hatch period. If you use products with ingredients 
that do not provide a long period of control, such as 
insecticidal soap or horticultural oil, you may need 
to retreat more often. 
Always monitor your plants for signs of phytotox-
icity (pesticide spray injury), such as discoloration, 
browning or leaf drop. To monitor the success of 
the foliar spray, look for newly settled young scale 
insects developing on leaves after treatments.
***
All pesticides are potentially hazardous to human 
health and the environment.  
As a pesticide user, you are legally required to 
read and carefully follow all directions and all safety 
precautions on the container label. Label instruc-
tions are subject to change, so read the label careful-
ly before buying, using and disposing of any pesti-
cide. Regardless of the information provided in an 
Extension publication, always follow your product’s 
label.  
When in doubt about any instructions, contact 
your pesticide seller, or the manufacturer listed on 
the label, for clarifi cation. All pesticides should be 
stored in their original labeled containers and kept 
out of the reach of children. Never pour leftover 
pesticides down a storm drain or any other drain.
Acknowledgments
The authors are grateful to Carlos Bogran and 
Scott Ludwig for review comments; to Gary Plaia 
of Katy, TX, for monitoring scale crawler hatches 
and reporting success in treating infested hollies in 
southeast Texas; and to Chris Fox for providing sug-
gestions of nonhost ornamental plant alternatives to 
hollies.
The information given herein is for educational purposes only. Reference to 
commercial products or trade names is made with the understanding that 
no discrimination is intended and no endorsement by the Texas AgriLife
Extension Service is implied.
   Produced by AgriLife Communications
       The Texas A&M System
Extension publications can be found on the Web at:
http://agrilifebookstore.org
Visit the Texas AgriLife Extension Service at:
http://texasextension.tamu.edu
Educational programs of the Texas AgriLife Extension Service are open to all people without regard to race, color, sex, disability, religion, 
age or national origin.
Issued in furtherance of Cooperative Extension Work in Agriculture and Home Economics, Acts of Congress of May 8, 1914, 
as amended, and June 30, 1914, in cooperation with the United States Department of Agriculture. Chester P. Fehlis, Deputy 
Director, Texas AgriLife Extension, The Texas A&M System.
7.5M, New


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Florida Wax Scales: Control Measures in Texas for Hollies

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Florida Wax Scales: Control Measures in Texas for Hollies

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