Entomology – Symptoms

Chewing Chew off external parts of a plant Grind them up Swallow solids and liquid parts together Grazing

Chewing Cabbageworms Armyworms Grasshoppers Colorado potato beetle Pear slug (sawfly) cankerworm Pear Sawfly

Cabbageworm Artogeia rapae                                  

Army Cutworm Euxoa auxiliaris

Clearwing Grasshopper

Pear Slug Caliroa crasei

Piercing-Sucking Piercing the epidermis and sucking out the sap from the cells within Internal and liquid portions of the plant are swallowed Insects remains on the plant

Piercing-Sucking Have an extremely slender and sharp pointed portion of the beak Thrust into the plant Sap is sucked

Piercing –Sucking effect Minute spotting or white, brown or red Leaves Fruit Twigs Curling of the leaves Deformed fruit Wilting, browning and dying

Piercing - Sucking Aphids, Scale insects Leafhoppers Squash bug Plant bug

Aphids

Aphid Curling & Distortion                                                                                                            

Aphids on Geranium

Brown Scale & Honeydew Coccus hesperidum

Leafhopper

Potato leafhopper damage

Squash Bug

Internal Feeders Feed within the plant tissues a part of all of their destructive stages Gain entrance by having eggs deposited into the tissues Eating their way in once the eggs hatch Hole is very minute (invisable) Large hole indicates the exit of the insect

Internal Feeders Borers Worms Leaf miners Gall insects

Ash Borer

Leaf Miners Small enough to feed between the upper and lower epidermis of a leaf

Gall insects Sting the plant which then grows a home for them Insects find shelter and food inside the gall Development from the secretions of the larvae Different insects on same plant make different structured galls

Cooley Spruce Gall

Chokecherry Midge in Gall

Subterranean Insects Attack roots and underground stems

Subterranean Insects Chewers Sap Suckers Root borers Gall insects Woolly apple aphid Wireworms Root maggots Billbugs

Laying eggs Puncture tissue as a place to lay eggs Cicada places eggs in 1 year twigs – splitting the wood Buffalo Tree Hopper

Use of Plants for Making Nest Leaf-cutter bees Take a semicircular piece of rose and other foliage Cemented together to form thimble-shaped cells In a tunnel made in the stem of a plant

Carry other insects to the plant and establishing them there

Insects Vector Pathogens Feed, lay eggs, or bore into plants Making an entrance point for disease Move pathogen on their bodies from one plant to a susceptible surface of another plant Carry pathogens on the outside or inside of their bodies and inject them as they feed

Insects Vector Pathogens Pathogens can spend time in the bodies of insects, can overwinter their Insects act as a host for a pathogen

Vectored Pathogens Dutch Elm Disease (fungus) Small Beetle Fireblight (Bacteria) Pollinating Insects Tomato Curly Top (virus) Beet Leafhopper Cucumber Mosaic (virus) Aphids