• Mouthparts pierce plant tissue and draw out fluid
• Importance:
– Usually low in forests
– Overuse of pesticides can incite damaging infestations
– Some deadly exotics in U.S.
– Some vector plant disease
• Often favor young succulent growth, high in nitrogen

Scales
Sucking insects: wide diversity
Lacebugs Adelgids
Mealybugs
Aphids
Thrips
Spittlebugs
Whiteflies
Thrips
Tree/leaf- hoppers

possible signs and symptoms
Honeydew sooty mold
Ants

possible signs and symptoms
Wooly ash aphid
Curled, discolored, and/or distorted foliage
Pink hibiscus mealybug
Thrips “stippling” on sweetgum

possible signs and symptoms
Waxy or cottony masses or coatings
Woolly pine scale
Asian wooly hackberry aphid
Flatid planthopper excretion
Pine bark adelgid

Sucking Insects: possible signs and symptoms
Twig and branch dieback
Kermes scale

Asian Wooly Hackberry Aphid Crapemyrtle Aphid
Oleander Aphid Giant Bark Aphid

Tuliptree scale
Oak Lecanium Scale
Scale “crawler”
Holly Pit Scale
Florida Wax Scale
Pine Needle Scale

Damaging Exotic Sucking Insects in Florida
Pick Hibiscus Mealybug
Lobate Lac Scale

An exotic eliminating eastern hemlocks

Factors that influence occurrence & impact: sucking insects
• Young succulent tissue
• Enhanced nutrient levels
• Overuse of broad-spectrum insecticides

sucking insects
• Do nothing
(let natural enemies do the job)
• Inspect for evidence of ladybugs, lacewings, other natural enemies
• Hard jet of water
(periodic, safe on natural enemies)
• Insecticidal Soaps (e.g., Safer’s, M-Pede,homemade)
– Disrupts cuticle, must cover pest, target scale crawlers
• Horticultural oils
(e.g., SunSpray Ultra-fine oil)
– Act by suffocation, must cover pest, target scale crawlers
• Systemic Insecticides
(e.g. Imidacloprid)
– as root drench, trunk injection

• Abnormal plant cell growth stimulated by another organism
– wasps, midges, aphids & mites
– Bacteria, fungi, nematodes
• >2000 gall producing-insects in the United States
– 60% occur on the oak family
• Primarily of aesthetic concern
• Stem galls may kill shoot

Oak Apple Gall
• Spherical galls on oaks in spring, summer
• Alternating wasp generations
– Adults emerge from galls, mate, female lays eggs in roots
– Female wasps emerge from roots in 2 nd spring, lay egg in leaf midrib
Amphibolips confluenta

• Caused by cynipid wasps
– Callirhytis spp.
• Laurel, water, other oaks
• Alternating twig and leaf gall stages
• Dense laurel oaks on poor sites
One wasp emerges from each “horn”

• Spongy galls on ends of new cypress growth
• Orange larvae inside, overwinter
• Galls drops with foliage in winter

• Appreciate the beauty
• Prune and destroy galls containing active life stages
• Plant site-appropriate tree species
• Conserve natural enemies through limited pesticide use