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Sucking and Gall Forming Insects

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					Sucking and Gall-Forming Insects
                 Sucking Insects
• 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
         Sucking insects: wide diversity
Scales           Lacebugs              Adelgids




                 Thrips                Spittlebugs
Mealybugs



                              Thrips

Aphids           Whiteflies            Tree/leaf- hoppers
Sucking Insects: possible signs and symptoms
          Honeydew




                             sooty mold




               Ants
Sucking Insects: possible signs and symptoms
                                       Wooly ash aphid
 Curled, discolored,
 and/or distorted foliage

 Pink hibiscus mealybug




                            Thrips “stippling” on sweetgum
Sucking Insects: 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
                         Aphids




Asian Wooly Hackberry Aphid   Crapemyrtle Aphid




        Oleander Aphid                 Giant Bark Aphid
          Scales                              Tuliptree scale




                            Scale “crawler”



Oak Lecanium Scale
                                              Holly Pit Scale




        Florida Wax Scale
                                          Pine Needle Scale
Sycamore Lace Bug
Damaging Exotic Sucking Insects in Florida
           Pick Hibiscus Mealybug




                                    Lobate Lac Scale
Hemlock Woolly Adelgid
An exotic eliminating eastern hemlocks
Factors that influence occurrence & impact:
               sucking insects

 • Young succulent tissue
 • Enhanced nutrient levels
 • Overuse of broad-spectrum insecticides
     Management: 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
           Galls
• 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 2nd spring,
      lay egg in leaf midrib




Amphibolips confluenta
                                   One wasp
                                   emerges from
  Horned Oak Gall                  each “horn”


• Caused by cynipid wasps
   – Callirhytis spp.
• Laurel, water, other oaks
• Alternating twig and leaf gall
  stages
• Dense laurel oaks on poor
  sites
    Cypress Twig Gall Midge
• Spongy galls on
  ends of new
  cypress growth
• Orange larvae
  inside, overwinter
• Galls drops with
  foliage in winter
          Management: galls
• Appreciate the beauty
• Prune and destroy
  galls containing
  active life stages
• Plant site-appropriate
  tree species
• Conserve natural
  enemies through
  limited pesticide use
Thanks Again!

				
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