Oklahoma Master Gardeners
Basic Entomology for
the Home and Landscape
Eric J. Rebek
Dept. of Entomology
and Plant Pathology
MG Questions and Answers
• How can I manage insect
pests without
insecticides?
• Why are my pine trees
dying?
• Do some plants repel
mosquitoes?
• Why doesn’t this
insecticide work?
Oklahoma State University
Oklahoma Master Gardeners
Keys to Insect Management
Know your landscape
Know your adversary
Know your tools for control
Oklahoma State University
Oklahoma Master Gardeners
Know Your Landscape
• Preemptive gardening
– good first step in keeping many
problems from ever occurring (i.e.,
preventative maintenance)
– proper plant material
– proper site identification
– proper fertility and watering
– overall, good horticultural practices to
maintain plant health
Oklahoma State University
Oklahoma Master Gardeners
Know Your Landscape
• Some insects are commonly
associated with certain plants
Oklahoma State University
Oklahoma Master Gardeners
Know Your Landscape
• Some of these close associations create a
nuisance for the home or landscape
Oklahoma State University
Oklahoma Master Gardeners
Know Your Landscape
• Location of materials in the landscape can
affect potential pest problems
Oklahoma State University
Oklahoma Master Gardeners
Know Your Adversary
Why Study BUG Science?
• Proper ID
• Associate injury symptoms with pest
• Selection of proper control strategy
Oklahoma State University
Oklahoma Master Gardeners
Classification of Japanese Beetle







Kingdom
Phylum
Class
Order
Family
Genus
Species
Oklahoma State University
Animalia
Arthropoda
Insecta
Coleoptera
Scarabaeidae
Popillia
japonica
Oklahoma Master Gardeners
The Arthropods
Phylum Arthropoda (ahr thrŏ pod a)
• The most abundant, diverse life form on
the planet (3/4 of known animal species)
• Our chief competitor for food, and a major
source of potential health problems and
annoyance
• Most are NOT a problem for us
Oklahoma State University
Oklahoma Master Gardeners
The Arthropods
• 100,000 species in North America
• 1,000 species in a typical backyard
• Mostly beneficial or harmless
– Pollination
– Food for birds, fish, frogs, etc.
– Produce honey, wax, shellac, silk
• Less than 2% are pests
– Destroy food crops, ornamentals
– Attack humans, livestock, and pets
– Transmit disease
Oklahoma State University
Oklahoma Master Gardeners
Arthropod Diversity
Other arthropods
Other insects
Hemiptera
Diptera
Hymenoptera
Coleoptera
Lepidoptera
What Is an Arthropod?
All arthropods have:
• Skeleton on the outside of the body
• Distinct body segmentation
• Paired, jointed appendages
• Dorsal, tubular heart valves
• Double, ventral nerve chord
• Open circulatory system
Oklahoma State University
Oklahoma Master Gardeners
Classes of Arthropods
• Malacostraca (crayfish, lobsters, sowbugs
pillbugs)  crustaceans
• Arachnida (spiders, mites, ticks, scorpions)
• Chilopoda (centipedes)
• Diplopoda (millipedes)
• Insecta (true bugs, beetles, butterflies,
wasps, fleas, grasshoppers, silverfish, etc.)
Oklahoma State University
Oklahoma Master Gardeners
The Arachnids
Class Arachnida (a-rach’-nid-a)
– Two body regions
(cephalothorax + abdomen)
– No antennae, never winged
– 4 pairs of legs
Tick
Oklahoma State University
Mite
Harvestman
Spider
Oklahoma Master Gardeners
Scorpion
The Chilopods
Class Chilopoda (chi lo po da)
Centipedes
– Two main body regions
– Flattened body
– 30 to 340 legs (1 pair
per body segment)
– 1 pair antennae
– Predaceous, can be venomous
Oklahoma State University
Oklahoma Master Gardeners
The Diplopods
Class Diplopoda (dip lo po da)
Millipedes
–
–
–
–
2 body regions
Body generally rounded
1 pair of antennae
80-400 legs (2 pair per
body segment)
– Feed on decaying organic
matter
– Often coil when disturbed
Oklahoma State University
Oklahoma Master Gardeners
The Insects
Class Insecta (in sec ta)
• Beetles, wasps, butterflies, cicadas,
grasshoppers, roaches
• 3 body regions
(head + thorax + abdomen)
• 3 pairs of legs
• 1 pair of antennae
• 0, 1 or 2 pair of wings
Oklahoma State University
Oklahoma Master Gardeners
Insect Physiology 101
The insect body is made of a substance called chitin;
it must be shed for the insect to grow
Oklahoma State University
Oklahoma Master Gardeners
Insect Growth
Metamorphosis
• Series of changes an insect passes through
in its growth and development
• Growth and development occur through the
process of ecdysis (shedding the
exoskeleton, or molting)
• Each molt allows insect to get bigger,
change shape, and mature
Oklahoma State University
Oklahoma Master Gardeners
Insect Growth
• Ametabolous Growth
– Increase in size, but no changes in
characteristics of the insect
Oklahoma State University
Oklahoma Master Gardeners
Insect Growth
• Ametabolous Growth
–
–
–
–
Protura (Proturans)
Diplura (Diplurans)
Thysanura (Silverfish)
Collembola (Springtails)
Oklahoma State University
Oklahoma Master Gardeners
Insect Growth
• Paurometabolous Development = gradual
metamorphosis
– Three life stages (egg, nymph, adult)
– Change in size, and addition of adult structures,
such as reproductive organs, wings.
Oklahoma State University
Oklahoma Master Gardeners
Insect Growth
• Gradual Metamorphosis
-
Isoptera (Termites)
Dermaptera (Earwigs)
Phthiraptera (Lice)
Psocoptera (Booklice)
Zoraptera (Angel insects)
Oklahoma State University
Oklahoma Master Gardeners
Insect Growth
• Gradual Metamorphosis
- Orthoptera (Grasshoppers,
Roaches, Walkingsticks,
Mantids)
- Thysanoptera (Thrips)
- Hemiptera (True Bugs, Aphids,
Scales, Leafhoppers, Plant
Hoppers, Whiteflies)
Oklahoma State University
Oklahoma Master Gardeners
Insect Growth
• Hemimetabolous Development =
simple (incomplete) metamorphosis
– Three life stages (egg, naiad, adult)
– Immature stage is aquatic
Oklahoma State University
Oklahoma Master Gardeners
Insect Growth
• Incomplete Metamorphosis
- Ephemeroptera (Mayfly)
- Odonata (Dragonfly)
- Plecoptera (Stonefly)
Oklahoma State University
Oklahoma Master Gardeners
Insect Growth
• Holometabolous Development =
complete metamorphosis
– Four life stages (egg, larva, pupa, adult)
Oklahoma State University
Oklahoma Master Gardeners
Insect Growth
• Complete Metamorphosis
- Neuroptera (Lacewings)
-
Coleoptera (Beetles)
Mecoptera (Scorpionfly)
Lepidoptera (Butterfly)
Diptera (True Fly)
Siphonaptera (Flea)
Hymenoptera (Ants, Bees, Wasps)
Oklahoma State University
Oklahoma Master Gardeners
Insect Orders
• Insects can be grouped into orders quite
easily with a bit of practice. Key in on
the following:
–
–
–
–
Wing type and number
Mouthparts
Type of development
Other body structures (legs, antennae, etc.)
Oklahoma State University
Oklahoma Master Gardeners
Insect Mouthparts
Chewing
Oklahoma State University
Oklahoma Master Gardeners
Insect Mouthparts
Chewing-lapping
Honeybee
Oklahoma State University
Sponging
House fly
Oklahoma Master Gardeners
Insect Mouthparts
Piercing-sucking
Leafhopper
Stable Fly
Mosquito
Flea
Louse
Oklahoma State University
Oklahoma Master Gardeners
Insect Mouthparts
Siphoning
Butterfly
Oklahoma State University
Rasping
Thrips
Oklahoma Master Gardeners
Insect Wings
True bug - hemelytra
Grasshopper - tegmina
Thrips – fringed
Beetle - elytra
Oklahoma State University
Wasp – membranous
Oklahoma Master Gardeners
Antennae
Oklahoma State University
Oklahoma Master Gardeners
Legs
Oklahoma State University
Oklahoma Master Gardeners
Major Groups of Insects
• Coleoptera (= sheath-winged) - Beetles
Complete
metamorphosis
Chewing
mouthparts
Hardened wing
covers (elytra) on
adults, antennae
are various
Oklahoma State University
Oklahoma Master Gardeners
Major Groups of Insects
• Diptera (= two-winged) - Flies,
gnats, mosquitoes
Complete metamorphosis
Mouthparts various
1 pair of membranous
wings, and 1 pair of little
knobs called halteres
(= hindwings)
Oklahoma State University
Oklahoma Master Gardeners
Major Groups of Insects
• Hemiptera (= half-winged) - True bugs
Gradual metamorphosis
Piercing-sucking
mouthparts
2 pairs of wings with
hemelytra (outer wings);
half membranous and
half leathery
Oklahoma State University
Oklahoma Master Gardeners
Major Groups of Insects
• Hemiptera - Aphids, scales, whiteflies,
leafhoppers, cicadas
Gradual metamorphosis
Piercing-sucking mouthparts
2 pairs of clear wings, some
wingless
Some reproduce without
males
Oklahoma State University
Oklahoma Master Gardeners
Major Groups of Insects
• Hymenoptera (= membrane-winged) Ants, bees, wasps
Complete
metamorphosis
Chewing mouthparts
Membranous wings
Oklahoma State University
Oklahoma Master Gardeners
Major Groups of Insects
• Lepidoptera (= scale-winged) Butterflies, moths, skippers
Complete
metamorphosis
Siphoning mouthparts
(adult), chewing
mouthparts (larva)
2 pairs of wings with
colored scales
Oklahoma State University
Oklahoma Master Gardeners
Major Groups of Insects
• Orthoptera (= straight-winged) Grasshopper, cricket, praying mantis,
walkingstick,
cockroach
Gradual metamorphosis
Chewing mouthparts
Outer wings leathery,
inner ones membranous
Oklahoma State University
Oklahoma Master Gardeners
Major Groups of Insects
• Neuroptera (= nerve-winged) - Lacewings,
antlions, snakeflies, mantispids, dobsonflies
Complete metamorphosis
Chewing mouthparts
(adult), piercing
mouthparts (larva)
Membranous wings with
many veins
Most are predaceous
Oklahoma State University
Oklahoma Master Gardeners
Major Groups of Insects
• Thysanoptera (= fringe-winged) –
thrips
Gradual metamorphosis
Rasping-sucking
mouthparts
2 pairs of “feathery”
wings
Oklahoma State University
Oklahoma Master Gardeners