Beneficial and Harmful Insects Plant Pest Beneficial and Harmful Insects

Objectives Compare and Contrast complete and incomplete metamorphosis. Identify and describe beneficial insects. Identify and describe harmful insects. **For this lesson you will need to take notes on the different insects mentioned**

Introduction Plants naturally have inherited problems These plants rarely can be cured. The best way to avoid this is to choose plants best adapted for the region. Florida has more different kinds of insects that any other state.

Introduction (continued) Most insects are NOT harmful to our plants. Harmful insects are harmful due to: Feeding Habits Breeding Shelter Habits

Insect Lifecycles Complete Metamorphosis Metamorphosis: when insects pass through several stages during development. Complete Metamorphosis 4 stages: Egg, Larva, Pupa, Adult Examples: Butterflies Mealworms Ladybugs

Incomplete Metamorphosis 3 Stages: Egg Nymph Adult Examples: Stinkbugs Earwigs Grasshopper Cockroaches

Beneficial Insects Less than one half of one percent are actually pests. Many beneficial insects feed on insects that are pests. Example: Spiders, Assassin Bugs, Praying Mantids, Lacewings, Parasitic Wasps

Ladybeetles Florida’s most beneficial insect!! Both adults and larva prey on Aphids Adults: oval, red and black, or black/yellow Adult eating Aphid Full Grown Larva Ladybeetle Eggs

Praying Mantids Very large insects (up to 2” in length) Can be either green or brown Front legs modified for grasping prey Feed on flies, honeybees, crickets & moths Adult Praying Mantis Egg case (ootheca) and Larva

Assassin Bugs Generally black or brown (can be bright) Found on foliage where they attack prey Caterpillars are their favorite lunch!! Typically ambush their prey.

Lacewings Commonly found on grasses, row crops, shrubs and trees. Feed on Aphids which nicknames them “Aphidlion” Green with copper eyes

Parasitic Wasps Extremely important insects!! Very small (1/8”) and go unnoticed They lay eggs on the body of a host insect Immature stage consumes the host Prey on: Scales, Whitefiles, Aphids, Leafminers and caterpillars

Spider Rarely Bite Humans! Predaceous, feed on a wide variety of insects Paralyze their prey with a venom bite Most use webs but most beneficial spiders do not spin webs. Examples: Wolf, Jumping and Crab

Insects as Pests (Harmful) Pests of plants are typically divided into groups according to the way they damage plants Most insects damage plants with their mouthparts. Piercing-Sucking Mouthparts Chewing Mouthparts (Foliage Feeding Insects)

Piercing Sucking Mouthparts Tube like mouthpart which inserts into a food source Plant, other insect, humans etc. Cause damage to plants: Stunting Yellowing Often are not affected by exterior pesticides as they feed on the interior of leaves

Chewing Mouthparts Feed on leaves, flowers and also attack the roots of plants. Mouthparts move side to side similar to scissors. Examples include: Caterpillar Beetle Grasshopper Katydids

Scales (p.s.) Most serious pests on many ornamental plants. Many species of soft and hard scales in Florida. Cause yellow spots to appear on the top sides of leaves Secrete a waxy covering over their bodies when mature making them hard to control.

Mealybugs (p.s.) Pests to foliage plants, annuals and perennials. Excrete honeydew which serves as medium for fungus. Soft bodied Scale Common on: Azalea Coleus Croton Cactus

Aphids (p.s) Pear shaped Will infest any plant Cause damage by sucking out plant juices Transmit viral diseases Mostly female and reproduce without mating Each produce 50 – 100 daughters which reproduce in 8 days!!

Whiteflies Common on ornamental plants Resemble moths Plants become pale or spotted Can transmit viruses Deposit eggs on underside of leaves Eaten by Lady Beetles and lace wings

Lacebugs (p.s.) Brown with clear wings. Damage on top side of leaf as white specks Shiny black spots of excrement on underside of leaves Cause damage to: Azalea Hawthorns

Thrips (p.s) Very small and slender Remove plant juices Life cycle takes 2-4 weeks Foliage feeders Infested plants have stippled appearance and small brown specks.

Caterpillars (ch) Immature stage of moths/butterflies Vary in color and hair stinging rose  Devour foliage leaves holes and irregular areas or can strip leaves completely

Grasshopper and Katydid (ch) Consume large quantities of foliage on ornamentals Adults lay eggs clumped together in pods (in soil) 1 complete life cycle per year Feeding habits vary greatly

Beetles (ch) Hard shelled insect Chew off parts of the foliage or flowers of many plants. Mostly active at night. Larvae feed on the roots or bore through stems and branches.

Plant Insect Awareness Project: Most people are unaware of the harms and benefits of the many insects that reside in Florida. You are to create a Public Awareness Poster and insect model for your specific insect. This is a two part project: Part 1: Create a poster displaying facts about either your Beneficial or Harmful insect Part 2: Create a model of the insect using a variety of materials.

Plant Insect Awareness Project Things to include on your poster: Life cycle of insect Description of insect Harms or Benefits Where found (plants) Things to include for your insect model: Needs to be actual model of insect!! Including proper mouthparts, legs, body segments, eyes, etc. You may use a variety of materials (clay, foam, putty, food, straws etc. ) Points for the project are as follows: -Pest Awareness Poster: 25 points -Pest Model: 15 points Total Points: 40 points

List of possible insects: Harmful: -Scales -Mealybugs -Aphids -Whiteflies -Lacebugs -Thrips -Caterpillars -Grasshoppers -Katydids -Beetles Beneficial: -Ladybeetles -Praying Mantids -Assassin Bugs -Lacewings -Parasitic Wasps -Spiders