Common Insect Problems - (PowerPoint)

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Common Insect Problems Garden Center Spring
Tune-Up2002

• Gus Lorenz, Ext. Entomologist- IPM Coordinator
• Don Johnson, Ext. Entomologist- Section Leader

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The Keys to Insect Management

• Correct identification of the pest is essential
  in determining the right control.
• Understanding the life cycle of the insect will
  help you in the tactics used for control.
• If insecticides are required be sure to read the
  label and follow the directions.

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Lacebugs
Lacebug Nymphs

• Insects feed on underside of
• leaf.
• Damage often confused with
• leafhopper or mite injury.
• Look for characteristic brown
• patches (excrement) on
• underside of leaf and cast
• skins of nymphal stage.
• Hosts Azalea, pyrcantha, and
• sycamore.
• Insecticides for control
• Orthene, Cygon, Sevin,
• Diazinon, Insecticidal Soaps

Lacebug Adults
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Lacebug Damage
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Armored or Hard Scales
male

• Easily identified by oval or
• oblong-shaped helmets on
• underside of leaf.
• Easily controlled only in
• nymphal stage before the shell
• is developed.
• Damage characterized by
• distinctive yellow splotching on
• upper side of leaf.
• Damages plant by weakening
• the plant and defoliation.
• Hosts include Euonymus,
• Magnolia, and Maple
• Insecticides recommended
• Cygon, Orthene, Malathion, and
• Dormant Oils.

female
nymph
Euonymus Scale
Scale Damage
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Nymphal Stage of Scales
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Soft Scales
Hemispherical Soft Scale

• Similar to hard scales in many
• ways except the covering is
• usually white or off-white waxy
• Sac-like covering or a bump as
• seen with Hemi.
• With soft scales usually have
• honeydew and sooty mold.
• Scale Test for Hard or Soft is
• that if you can flick it off with
• your finger without disturbing
• the plant tissue-it is a scale. If it
• will not flick off it is probably a
• gall.
• Host range azalea, euonymus,
• boxwood, maple, pine.
• Control same as for armored.

Florida Soft Wax Scale
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Soft Scale on Tulip Poplar
Female
Note sooty mold from Honeydew excretion
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Whiteflies

• Infestations often noted when
• plant is bumped and a cloud of
• snow flake-like adults fly from the
• plant. Plant with dandruff.
• Although usually associated with
• GH, can thrive outside in summer.
• Infested plants turn yellow when
• heavily infested and as seen with
• aphids and soft scales honeydew
• causes sooty mold to develop on
• leaves.
• Hosts include azalea, fuchsia.
• Control recommendations sticky
• traps, azadiractin, soils, oil,
• Orthene, cygon, malathion,
• resmethrin

Whitefly Nymphs
Whitefly Adult
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Whitefly Damage to Poinsettia
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Spider mites

• Very small arthropod. Same group as ticks and
  spiders.
• Symptoms are bronzing or flecking of leaves,
  webbing in severe
• Infestations.

• Hosts include marigold, junipers,
• boxwood, burning bush

Two spotted spider mites

• Control azadiractin, Dicofol
• Kelthane.

Spider mite damage
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Typical Spider Mite Damage
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Turf Mites
Bifenthrin and fluvalinate are 2 new chemicals
for control.
Bermuda grass mite
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Turf Grubs

• White grubs tend to infest same area year after
  year.
• One generation per yr.
• Adults emerge June and lay eggs
• Overwinter as larvae
• Diazinon, dursban, Mach II, Merit for control.

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Borers

• Typically a problem on stressed plants.
• Hosts Maples, Ash, Lilac, Pines, Birch
• Hard to control. Best way is to keep plants
• as healthy as possible to keep their defenses
• up.
• New species causing severe problems in U.S.

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Asian Lonhorned Beetle
Cottonwood Borer
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Asian Longhorned BeetleAnoplophora glabripennis

• First discovered in Brooklyn, NY in 1996.
• In July workers have begun chopping down,
  chipping and burning infested trees 4,958 trees
  have been destroyed.
• Recent infestations found in CA, SC, IL, and in
  Canada. In Chicago 1,434 trees destroyed.
• China is now cooperating by fumigating with
  Methyl Bromide, 90 compliance.

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Asian Longhorned BeetleAnoplophora glabripennis

• In China referred to as the Starry Sky beetle
  because of the white, celestial markings on its
  black body.
• Often confused with the cottonwood borer another
  closely related cerambycid.
• Native to Japan, China, and Korea.
• Natural range broad enough to guarantee it can
  live throughout most of North America.
• Threat in Arkansas to ornamental trees.

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Red Oak Borer, Enaphalodes rufulus

• Native to N. America
• Permanent damage to wood of
• living oak trees causes a decrease
• in lumber grade up to 40
• Affects about 38 of oak wood
• in eastern U.S.
• Alarming increase in numbers
• resulting in mortality of red oaks
• throughout Ozark and Ouachita
• National Forests.
• Mortality thought to be related to
• drought during growing season.

Red oak borer adult
ROB gallery
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Asian Ambrosia Beetle
Xylosandrus crassiusculis

• First detected in S.C. peaches, 74
• Spread to NC (79)MS (80)AL,FL
• (83) TX (84)GA, LA,MD,TN
• (93) OK (94) VA, OR (95)
• Hosts include pecan, peach, plum,
• persimmon, golden raintree, sweet
• gum, Shumard oak, magnolia, fig,
• Chinese elm, sweet potato, others

adult
damage
Infestation Symptoms
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Asian Ambrosia Beetle (cont)

• Female bores into all above ground parts of host.
  Carries blue-stain fungi similar to other
  scolytids. Infest healthy, stressed or freshly
  cut hosts.
• Eggs, larvae, and pupae found together in
  galleries excavated by adult female.
• Males are rare, small and flightless.
• Large numbers of attacks result in death of host.
• Morrilton, AR site of Arkansas infestation. Pecan
  trees 3-4 yrs old are extremely susceptible to
  death. Grower lost significant number of trees.

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Leafminers and the Damage They Cause
Serpentine Leafminer
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Leafminers

• Diverse group including flies, beetles, moths,
  and sawflies.
• Feed between the upper and lower surface of leaf.
  Obviously very small insects.
• Damage usually cosmetic only.
• Hosts includeboxwood, locust, arborvite,
  columbine, holly, privet.
• Recommended for controlCygon, Orthene.
• Most times control is not needed and not
  effective.

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Arborvitae Leafminer
Leafminers
Columbine Leafminer
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Bagworms

• Larval stage provides itself home
• and protection from predators.
• Usually just an aesthetic issue.
• Bags can be used for Christmas
• ornaments.
• Hosts include juniper, arborvitae.
• Control recommendations
• Pick them off, BT (Bacillus
• Thuringiensis, malathion, orthene.

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Aphids
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Aphid Infestation and Associated Damage
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Aphids

• Usually found on succulent part of plants. Can
  be many colors.
• As with soft scales and whiteflies, honeydew can
  cause sooty mold.
• Feeding also causes deformed and withered leaves.
  Vectors many
• Viruses.

• Tremendous ability to reproduce. Life cycle about
  3 days.
• Hosts includeRoses, Pyrcantha, English Ivy,
  Birch, Crape Myrtle
• Control soaps,
• Azadiractin, orthene,
• Malathion.

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Japanese BeetleStatus 2002
Arkansas State Plant Board has been monitoring
movement into Has been in Arkansas for the last
several years. No significant increase in
distribution.
Positive trap catches in Washington, Benton
(1140), Greene, Clay,White (132), Faulkner (275),
Pulaski, Arkansas, and Columbia Counties.
Infestation of the state is inevitable.
Infestations reported last year in NW Arkansas.
Excellent Extension brochure available on
Japanese Beetle made possible by support of
APHIS and ASPB.
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Keep the Good Guys in Mind