2. I. Introduction to Insects A. Exoskeleton B. Molting C. Distinct growth cycles D. Eggs E. Metamorphosis II. Growth Stages A. Simple Metamorphosis 1. Gradual 2. Egg, nymph, and adult 3. Grasshoppers, crickets, thrips, bugs, leafhoppers, & aphids 4. Look like small adults but nymphs do not have fully formed wings Turf Diseases and Insects – Turf 215
3. II. Growth Stages - con’t B. Complex Metamorphosis 1. Egg, larva, pupa, adult Turf Diseases and Insects – Turf 215
4. II. Growth Stages - con’t B. Complex Metamorphosis 1. Egg, larva, pupa, adult 2. Young stage is the larva 3. Larva look nothing like the adult 4. Larva does the most feeding and is the most destructive 5. Butterfly, moth, sawfly, and fly - adults do not damage 6. Beetle - both larva and adult 7. Adults Larva Moths and butterflies caterpillars, inchworms, loopers leafminers, cutworms, borers, Beetles grubs, wireworms, borers, billbugs Flies maggots, grubs, leafminers Turf Diseases and Insects – Turf 215
6. III. Insect Physiology and Structure A. Respiratory and nervous system 1. Breath through small openings (called SPIRACLES) in the side of their bodies 2. Some controls work by blocking this opening 3. Central Nervous system - OP and Carbamates a. Cholinesterase inhibitors 4. Warning - Higher toxicity to humans because of similarities in physiological structures Turf Diseases and Insects – Turf 215
7. III. Insect Physiology and Structure B. External Structure 1. Insects have a three part body a. head b. thorax c. abdomen Turf Diseases and Insects – Turf 215
8. III. Insect Physiology and Structure B. External Structure 1. Insects have a three part body a. head b. thorax c. abdomen 2. Six legs that are attached to the thorax 3. In winged forms, 1 or 2 pairs of wings 4. One pair of antennae 5. Arachnids - spiders, mites, and ticks 6. Body divided into 2 regions - cephalothorax and abdomen 7. Four pairs of legs attached to the cephalothorax 8. No wings 9. No antennae Turf Diseases and Insects – Turf 215
9. III. Insect Physiology and Structure B. External Structure 5. Arachnids - spiders, mites, and ticks Turf Diseases and Insects – Turf 215
10. III. Insect Physiology and Structure C. Mouthparts 1. Chewing mouthparts rip and chew food - grasshoppers, beetles, weevils, sawflies, and caterpillars 2. Piercing and sucking mouthparts pierce plants and suck liquid materials - leafhoppers, stink bugs, aphids, and mites Turf Diseases and Insects – Turf 215
11. III. Insect Physiology and Structure C. Mouthparts 1. Chewing mouthparts rip and chew food - grasshoppers, beetles, weevils, sawflies, and caterpillars 2. Piercing and sucking mouthparts pierce plants and suck liquid materials - leafhoppers, stink bugs, aphids, and mites D. Wings 1. Usually only found on adults - number of 2. Descriptive type Turf Diseases and Insects – Turf 215
12. IV. Insect Relatives A. Spiders 1. All spiders are toxic 2. Most cannot bite humans mouth is to small B. Mites 1. Most have sucking mouth parts 1. Centipede type root feeder 3. Most are beneficial C. Symphlans Turf Diseases and Insects – Turf 215
13. V. Damage caused by insects A. Chewing damage - defoliation B. Internal feeders C. Sucking pests - plant juices D. Disease transmission E. Subterranean feeders F. Secondary plant pests G. Plant reaction to insect attack 1. Pine trees - sap (meant to cover or kill the insect 2. Galls Turf Diseases and Insects – Turf 215
14. VI. Factors influencing pest problems A. Unfavorable weather conditions B. Natural enemies 1. predators 2. parasites 3. parasitoids Turf Diseases and Insects – Turf 215
