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Lace Bugs on Ornamental Plants 1
Eileen A. Buss and Jay Cee Turner2At least 17 species of lace bugs (Heteroptera: Tingidae) are pests of trees and shrubs in the eastern United States (Table 1 ). Most lace bug species have a limited host range and may attack only a handful of plant species. Plants that are commonly attacked include azalea, hawthorn, lantana, oak, pyracantha and sycamore.
Biology and Behavior
Lace bugs ( Figure 1 ) are small insects, 1/4 to 1/8 inch long, broad, flattened and somewhat rectangular in shape. Their bodies are usually brown or black, but their wings are partially transparent and lace-like. Immature lace bugs or nymphs ( Figure 2 ) are blackish in color, wingless, and have many small spines projecting from their body.
CREDITS: E. A. Buss, University of Florida
Figure 1. Azalea lace bug adult
Figure 2. Lace bug nymphs Females lay eggs on the lower leaf surface along the midrib or lateral veins and cover them with a brownish substance. These dark varnish- or molasses-like spots are obvious when plants are heavily infested. Most species have five nymphal instars before becoming adults. Each generation, from egg to adult, takes about 30 - 45 days. There may be three to five generations each year.
Lace bugs damage plants by inserting their piercing-sucking mouthparts into the underside of leaves and withdrawing chlorophyll and other plant fluids. Females generally cause more damage than males. The upper surface of lightly-infested leaves has a white-dotted, or stippled appearance ( Figure 3 ). Heavy infestations cause leaves to brown and drop prematurely, which reduces growth or kills the plant.
Figure 3. Lace bug damage on azalea Detecting Infestations
Examine your plants weekly during the spring, summer, and fall. Turn a few leaves over and look for lace bugs with a 10 to 15 power hand lens or shake an infested branch over a white sheet of paper. The insects will fall off and may be more easily identified than on the foliage. The brown spots and stippling may remain on leaves even after pest populations have been reduced.Cultural Control
Several non-chemical means of reducing lace bug problems exist. One option is to thoroughly spray infested plants with a high-pressure stream of water. However, this approach may only knock the insects off the plants, rather than kill them.Establish plants according to their growth patterns, keep them healthy, and well-watered. For example, azaleas, which are understory shrubs, tolerate less lace bug damage when planted in full sun and suffering from drought-stress.
Choose varieties or species of plants that are resistant to lace bugs or better tolerate damage.
Biological Control
Very few beneficial insects specialize on lace bugs. However, generalist predators, such as green lacewings, may attack lace bug nymphs and adults. Lace bugs may also be infected by diseases.Chemical Control
If more than 15% of the foliage is damaged, then an insecticide application is suggested (Table 2 ). Insecticidal soaps (e.g., Safer Soap, M-pede) are often a first line of defense against soft-bodied insects. In general, spray plants to run-off or until leaves (top and bottom) are thoroughly wet (check the label for application instructions). Continue to inspect the plants periodically and apply an insecticide if plants become re-infested. Soil treatments are relatively slow in action, but effective for up to 5 or 6 weeks. Systemic insecticides are absorbed more rapidly by plants when they are worked into the soil and watered.For More Information
- Avocado lace bug, EENY-039 (http://edis.ifas.ufl.edu/IN166 )
- Hawthorn lace bug, EENY-080 (http://edis.ifas.ufl.edu/IN237 )
- Lantana lace bug, EENY-246 (http://edis.ifas.ufl.edu/IN514 )
- Sycamore lace bug, EENY-190 (http://edis.ifas.ufl.edu/IN347 )
Tables
Table 1. Common species of lace bugs and their host plants in the eastern United States.
Common Name
Scientific Name
Hosts
Alder lace bug Corythucha pergandei*
Alder, birch, crabapple, elm, hazel Avocado lace bug
Pseudocysta persea
Avocado Azalea lace bug
Stephanitis pyrioides
Azalea Basswood lace bug Gargaphia tiliae
Linden, basswood Birch lace bug C. pallipes
Ash, beech, eastern hophornbeam, mountain maple, white birch, willow, yellow birch Buckeye lace bug C. aesculi
Buckeye Cherry lace bug C. pruni
Wild cherry Elm lace bug C. celtidis
American elm Hackberry lace bug C. celtidis
Hackberry Hawthorn lace bug C. cydoniae*
Hawthorn, pyrocantha , quince
Lantana lace bug
Teleonemia scrupulosa
Lantana Oak lace bug C. arcuata
Oak, maple Sycamore lace bug
C. ciliata*
Sycamore Walnut lace bug C. juglandis*
Black walnut, butternut, linden Willow lace bug C. mollicula
Willow Willow and poplar lace bug C. elegans
Balsam poplar, bigtooth aspen, quaking aspen, willow --
C. associata
Wild cherry --
C. bellula
Hawthorn --
C. marmorata
Basswood -- No common name exists * Found throughout the United States and parts of Canada
Table 2. Insecticides labeled for non-commercial (homeowner) use against lace bugs in Florida.
Table 3. Insecticides registered in Florida for professional use against lace bugs.
Chemical Name
Florida Registered Products
Chemical Class
Formulation*
Signal Word
Acephate Acephate Pro 75 Orthene Turf, Tree & Ornamental Spray
Organophosphate WSP
WSP
Caution Caution
Bifenthrin Talstar F Talstar GC Flowable**
Talstar Nursery Flowable**
Pyrethroid
F
F
F
Caution Caution
Caution
Carbaryl Sevin SL Sevin 80 WSP
Carbamate SL
WSP
Caution Warning
Cyfluthrin
Bayer Advanced Power Force Multi-Insect Killer
Tempo 20 WP GC WSP**
Tempo 20 WP Power Pak
Pyrethroid
WP
WSP
WSP
SC/WP
Caution Caution
Caution
Caution
Cyfluthrin + Imidacloprid
Discus
Pyrethroid + Neonicotinoid
F
Caution
Deltamethrin
DeltaGard GC 5SC** DeltaGard T&O 5SC
Pyrethroid SC
SC
Caution Fenpropathrin Tame 2.4 EC Spray** Fenpropathrin EC
Warning Fish Oil Organocide Biorational EC
Caution Horticultural oil
Sunspray Ultra Fine Oil Volck
Biorational EC
EC
Caution Caution
Imidacloprid Marathon 1% Marathon 60
Marathon II
Merit 2
Merit 2.5
Neonicotinoid
G
WP
F
F
G
WP/WSP
Caution Caution
Caution
Caution
Caution
Caution
Lambda-cyhalothrin
Demand CS Scimitar WP
Pyrethroid F
F
WSP
Caution Caution
Warning
Malathion Malathion 8 Malathion 8F
Organophosphate SL
EC
Caution Caution
Permethrin
Astro Permethrin Pro Termite-Turf Ornamental
Pyrethroid
EC
EC
Caution Caution
Potassium salts Insecticidal Soap 49.52 CF M-pede
Insecticidal soap F
F
Warning Caution
Thiamethoxam
Flagship
Neonicotinoid
WG
Caution
* EC=Emulsifiable concentrate; F=Water-dispersible liquid; G=Granule; SC=Water-soluble liquid; SL=Water-soluble liquid; WP= Wettable powder; WSP=Water-soluble powder ** Restricted use product.
Note: Only a few formulations of recommended insecticides are listed to serve as examples. Many others are available. Read the label carefully for use directions, application techniques, irrigation requirements and precautions.
Footnotes
1. This document is ENY-332 (MG326), one of a series of the Department of Entomology and Nematology, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Date first printed October 1993. Revised: June 2006. Please visit the EDIS Website at http://edis.ifas.ufl.edu.2. Eileen A. Buss, assistant professor and Jay Cee Turner, graduate student, Department of Entomology and Nematology, Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, 32611.
The use of trade names in this publication is solely for the purpose of providing specific information. UF/IFAS does not guarantee or warranty the products named, and references to them in this publication does not signify our approval to the exclusion of other products of suitable composition. All chemicals should be used in accordance with directions on the manufacturer's label. Use pesticides safely. Read and follow directions on the manufacturer's label.
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U.S. Department of Agriculture, Cooperative Extension Service, University of Florida, IFAS, Florida A. & M. University Cooperative Extension Program, and Boards of County Commissioners Cooperating. Larry Arrington, Dean.
Copyright Information
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