Foliage and Houseplant Insect Identification

1
Foliage and Houseplant Insect Identification
Management

• Phil Pellitteri
• UW Madison
• Insect Diagnostic Lab

2
Issues

• Almost all problems are tropical insects- most
  not found naturally in Wisconsin
• Most have wide host range
• Sensitive environments to treat
• Homeowners have limited products to pick from

3
Greenhouse and foliage plant insects are
difficult to manage

• Multiple generations - up to 20 / year
• Lack of natural enemies to reduce populations
• Almost unlimited food
• Constant environmental conditions
• Some life stages are not susceptible to
  treatment need multiple treatments
• Major insecticide and miticide resistance

4
Surinam Roach
5
American roach
Australian roach
6
Order Homoptera

• Aphids
• Mealybugs
• Scales
• Whiteflies

• Incomplete metamorphosis
• Sucking mouthparts
• Two pair of membranous wings

7
(No Transcript)
8
(No Transcript)
9
Mealybugs
10
(No Transcript)
11
Mealybug Life Cycle
12
Mealybug Damage

• Feed at stem tips and leaf junctures.
• Mostly on tropical foliage plants
• Stunting, yellowing, defoliation, wilting.
• Honeydew and sooty mold.
• Citrus mealybug can inject a toxin while feeding.

13
Honeydew
14
Honey Dew Sooty Mold
15
Mealybug Monitoring

• Visual inspection of leaves and stems
• Yellowed or wilted foliage may indicate
  underground infestations- African violets

16
Mealybug Chemical Control

• Use insect growth regulators (IGR) when
  beneficial insects are present.
• Need 2-3 treatments at 10-14 days - eggs and
  adults are somewhat protected
• Insecticidial Soap
• Permethrin
• Neem Oil, Beauvaria
• Bayer systemic

17
Mealybug IPM

• Inspect new plant material on arrival.
• Destroy heavily infested plants.
• Hand pick?

18
Mealybug Destroyer
19
Aphids

• Soft-bodied insects
• Wings present or absent
• Cornicles (tail pipes)
• Honeydew
• Sooty mold
• May transmit viruses
• Breed without mating-give birth to live young
• (5day generation time at 850f
• Reduces plant vigor, stunting, malformation

20
Aphid Life Cycle
21
Aphids

• Green Peach Aphid
• Cotton Aphid
• Potato Aphid
• Foxglove Aphid
• Melon Aphid

22
Green Peach Aphid on Peppers
23
Aphid Monitoring

• Check as many plants as possible
• Look at terminal buds and lower leaf surfaces
• Cast skins, honeydew, sooty mold are
  indications of aphid infestation.

24
(No Transcript)
25
Parasitized Aphids
26
Aphid killing fungus
27
Aphid IPM

• Sanitation
• Remove weeds
• Screen vents and windows
• Cultural
• Limit the use of quick-release fertilizer
• Beneficial Insects
• Green lacewings
• Ladybeetles
• Parasitic wasps

28
Aphid Chemical Control

• Insecticidial soap
• Resmethrin, pyrethrin
• Azatin, Avid, Beauvaria fungus

29
Whiteflies

• Immatures resemble scales.
• Examine lower leaf surfaces to detect nymphs/
  pupae.
• Greenhouse
• Sweet Potato
• Silverleaf
• Bandwing

30
Sweet Potato Whitefly
31
Whitefly Life Cycle
32
Whitefly Damage

• Honey dew sooty mold.
• Yellowing and wilting of leaves.
• Yield reduction of vegetables.
• Can transmit viruses to some hosts.
• Sweet potato/silverleaf have toxic feeding
  effects
• Poinsettia, fuchsia, Solanaceous plants

33
Whitefly

• Eliminate all plants, including weeds and pet
  plants for at least 1 week before starting a new
  crop.
• Inspect all new plant
• Screen vents - tropical insect that migrates into
  greenhouse in November
• Encarsia formosa parasitic wasp

34
Whitefly Chemical Control

• Start chemical control early.
• Treat every 5-7 days- total of three treatments.
• Watch for resistance
• If use chemicals

• Insecticidial soap
• Marathon - granular
• Sanmite
• Endeavor
• Avid
• Orthene
• Permethrin
• Tame
• Dursban
• Azatin

35
Soft vs. Armored Scales

• Soft Scales
• Larger size
• Cant separate shield
• Armored Scales
• Hard, waxy shield
• Shield separates easily

36
Soft Scales

• Brown soft scale
• Hemispherical scale
• Black scale
• Niger scale

37
(No Transcript)
38
Scale Life Cycle
39
Scale Crawlers Eggs
40
Hemispherical Scale
41
Oleander Scale
42
(No Transcript)
43
(No Transcript)
44
Scale Monitoring

• Visual inspection of lower leaf surfaces and
  stems.
• Yellowed foliage may indicate a scale
  infestation- or presence of honey dew on leaves.
• Foliage plant pest - wide host range.

45
Scale IPM

• Remove and destroy heavily infested plants.
• Wash off honeydew and dislodge crawlers with
  water sprays.
• Inspect new plant material on arrival.

46
Scale Chemical Control

• Spot treat if there are 2 or more adult scales or
  large numbers of crawlers per leaf.
• Need 2-3 treatments at 10 day intervals.
• Insect growth regulators (azadirachtin) and soaps
  will control soft scales.
• SYSTEMICS????????

47
Order Thysanoptera

• Thrips
• 4 narrow, fringed wings
• Tube-like mouthparts

48
Thrips

• Tiny insects that hide in flowers, buds, and leaf
  axils.
• WFT transmit the tomato spotted wilt virus
  impatiens necrotic spot virus.

49
Western Flower Thrips
50
Thrips Life Cycle
51
Thrips Feeding on Gladiolus
52
(No Transcript)
53
Thrips Damage

• Rasping mouthparts puncture plant surfaces.
• Egg-laying also damages plants.
• Injury appears in streaks rather than spots.
• Blossoms become brown.
• Petals are distorted.
• Buds fail to open.

54
Thrips Damage on Mums
55
Thrips Damage

• Look for wet, varnish spots in feeding injury
  sites
• Most of damage on flowers- and in new growth
• On underside of leaves of foliage plants

56
(No Transcript)
57
Use Blue Sticky Cards to Monitor Thrips
58
(No Transcript)
59
Thrips IPM

• Sanitation
• Remove weeds that act as a thrips refuge.
• Screen windows, vents, and fans.
• Pasteurize soil to kill immature thrips.

60
Thrips Chemical Control

• Treat at 3-5 day intervals with very good
  coverage
• Rotate chemicals to prevent resistance
• Spinosad (Conserve)
• Resmethrin
• SOAP?

61
(No Transcript)
62
(No Transcript)
63
Order Diptera

• Flies, gnats, mosquitoes, midges
• Fungus gnats
• Complete metamorphosis
• Adults a nuisance
• Larvae have chewing mouthparts and feed on roots,
  stems, fruit.

64
Fungus Gnats

• Distinguished by the long, many-segmented
  antennae.
• Weak flier
• Feed or decaying organic matter in potting mix,
  decaying plants

65
Fungus Gnat Adult
66
Fungus Gnat Life Cycle
67
Fungus Gnat Larvae
68
Fungus Gnat Damage
69
Fungus Gnat Larvae
70
Fungus Gnat Monitoring

• Place potato wedges on growing medium surface to
  monitor larval populations.
• Leave in place for 3-4 days then look for larvae
  feeding on cut surface.

71
Fungus Gnat Shore Fly IPM

• Eliminate breeding areas
• Drain wet areas.
• Remove all plant debris.
• Avoid over watering plants.
• Avoid over fertilizing plant which will promote
  algae growth.

72
Fungus Gnat Shore Fly Chemical Control

• Permethrin
• Nematodes for fungus gnat
• Gnatrol (B.T.I.)- Gnat out

73
Mites

• Spider mites
• Cyclamen mite
• Broad mites

74
Two-spotted Spider Mite

• Oval, yellow-green with two large, dark spots
• Webbing, bronzing, stippling
• Worse in hot, dry conditions
• Mites feed in protected plant parts-underside of
  leaves

75
Spider Mite Life Cycle
76
(No Transcript)
77
(No Transcript)
78
(No Transcript)
79
(No Transcript)
80
Spider Mite Chemical Control

• WASH LEAVES with Water
• Resistant to most insecticides need a Miticide
• INSECTICIDIAL SOAP

81
(No Transcript)
82
(No Transcript)
83
Cyclamen Mite

• Microscopic creatures.
• Hide inside buds flowers.
• Inject a toxin while feeding.
• Low temps and high humidity favors outbreaks.
• Damage mimics physiological disorders.

84
Cyclamen Mite Chemical Control

• Can be controlled in water bath 110 OF for 15
  minutes
• Avid
• Thiodan
• Miticides?

85
Broad mite

• Delphinium
• China aster
• Begonia, gerbera,verbena,zinnia
• Mums, fuschsia,
• marigold
• Apples

86
(No Transcript)
87
Broad Mite
88
Broad Mite Chemical Control

• More available on plant than cyclamen mite-
• Damage looks like herbicide
• Attacks 60 families of plants
• Avid
• Thiodan
• Miticides?
• Sulfur- not pyrethroids
• Eliminate weed sources-clean cultivation

89
Springtails- Order Collembola

• No wings
• Simple development
• Chewing Mouthparts
• Most have spring-like device
• 677 species in North America

90
Springtails
91
(No Transcript)
92
(No Transcript)
93
Springtails

• Feed on organic matter, not harm plants other
  than a customer concern
• Care than some drenches can prune roots
• Sign of contamination