Slide 1Slide 2Slide 3Slide 4Slide 5Slide 6Slide 7Slide 8Slide 9Slide 10Slide 11Slide 12Slide 13Slide 14Slide 15Slide 16Slide 17Slide 18Slide 19Slide 20Slide 21Slide 22Slide 23Slide 24Slide 25Slide 26Slide 27Slide 28Slide 29Slide 30Slide 31Slide 32Slide 33Slide 34Slide 35Slide 36Slide 37Slide 38Slide 39Slide 40Slide 41Slide 42Slide 43Slide 44Slide 45Slide 46Slide 47Slide 48Slide 49Slide 50Slide 51Entomology 462Ornamentals Pests:Sucking PestsDavid J. Shetlar, Ph.D.The “BugDoc”The Ohio State University, OARDC & OSU ExtensionColumbus, OH© October, 2004, D.J. Shetlar, all rights reservedWoody Ornamental Pest GroupsSucking PestsWoody Ornamental Pest GroupsSucking PestsThrips (Thysanoptera)True Bugs (Hemiptera)Plant/Leaf bugs, Lace BugsBug-like Insects (Hemiptera)Leaf/Plant/Tree hoppers, Psyllids, Aphids, Whiteflies, Mealybugs, ScalesMites (Acarina)Spider mites, Eriophyid mitesWoody Ornamental Pest GroupsSucking Pests - SignsWoody Ornamental Pest GroupsSucking Pests - SignsPlant Distortion -Leaf & stem twisting & curlingDead spotsExcrement Deposits -Tar spots - true bugs, lace bugs, thripsHoneydew & Sooty MoldFoliage Discoloration - Spots & StipplesYellowing & BronzingHoneylocust leaflet distorted.Cuban Laurel (Ficus) thrips leaf distortion.Sooty mold from scale honeydew.Tarspots from lace bugs.Woody Ornamental Pest GroupsSucking Pests - ThripsWoody Ornamental Pest GroupsSucking Pests - Thripseggs  nymph 1  nymph 2  “prepupa”  “pupa”  adult (larva) (larva)•Cause streaking of flowers or spotting of foliage.•Occasionally cause foliage distortion.•Usually produce tiny tar spots.•Have complicated life cycle with non-feeding “prepupa” and “pupal” stages.(Thrips specialists often call the nymphal stages “larvae” which should really be used with insects that have a complete life cycle!)There are actually few thrips that are common pests of ornamental plants. The pear thrips occasionally attacks sugar maple in the spring. In this case, overwintered adults insert eggs in the veins of expanding maple leaves. The damage causes the leaves to distort and ragged holes may be formed.Several species of flower thrips cause streaking and spotting of flower petals. These are most noticeable in roses and some perennials.The greenhouse thrips commonly damages a variety of broadleaf evergreens in southern states. Attacks result in bronzed foliage. Upon close inspection, the leaves will be covered with tiny tarspots and numerous speckles where cell contents were removed by the thrips.The privet thrips causes similar damage to privet in northern states. Leaves first appear yellowed and then turn bronze or brown.The Cuban laural thrips causes severe stunting, discoloration and folding of ornamental figs.Pear thrips on maple leaf.Flower thrips on leaf. Note small tarspots and blanching due to cell contents being removed.Woody Ornamental Pest GroupsSucking Pests – Plant/Leaf BugsWoody Ornamental Pest GroupsSucking Pests – Plant/Leaf Bugs•Usually feed by injecting salivary digestive juices into leaf tissues which cause round to irregular necrotic spots.•Adults form “tar spots” with excrement.•Heavy feeding by adults or nymphs on young foliage can cause severe foliar distortion.•Most overwinter as eggs inserted into host plant tissues though some overwinter as adults.•Adults have typical “bug” look.Ash plant bug adult.Fourlined plant bug, note damage below.Tarnished plant bug, a general plant pest.Tarnished plant bug damage & nymph.Plant bugs are commonly called leaf bugs and almost all have the typical bug shape with a pentagonal pronotum, a triangular mesonotum, and a diamond shaped area where the membrane areas of both forewings cross.Almost every plant has its own species of plant bug, but there are several species that are generalists feeders. The tarnished plant bug is common on a variety of woody shrubs, perennials and even annual flowers. The fourlined plant bug is common on smaller shrubs and perennials.Most plant bugs produce irregular damage spots by liquefying leaf tissues with their salivary secretions during feeding. When damage occurs to young, expanding leaves, the leaves can be severely distorted and stunted.The plant bugs produce tarspots rather than honeydew.Controls are rarely necessary, and if needed, applications of contact pesticides should be made before the young nymphs have had sufficient time to cause extensive leaf damage.Woody Ornamental Pest GroupsSucking Pests – Lace BugsWoody Ornamental Pest GroupsSucking Pests – Lace Bugs•Pronotum and wings modified into highly reticulated (lacy) surface.•Nymphs usually spiny.•Produce “tar spot” excrement.•Usually remain in groups on leaf undersurfaces.•Feeding produces yellow speckles on leaf surfaces.Azalea lace bug damage. Note conspicuous leaf speckling.Typical lace bug adult. Note tar spots.Lace bug nymphs.Sassafras lace bug adults. Most lace bug females attach their eggs to leaves with their excrement.Lace bugs that attack deciduous plants overwinter as adults. Those that attack broadleaf evergreens overwinter as eggs.There are many species of lace bugs which attack a variety of deciduous and evergreen broadleaf trees and shrubs. Several species (e.g., the hawthorn lacebug) infest a large number of plants, but most species have rather limited host preferences.Lace bugs that attack deciduous plants generally overwinter as adults under flaps of bark or in the leaf litter around their hosts. Lace bugs that attack broadleaf evergreens overwinter as eggs glued to host leaves with excrement (a tarspot like material).Most species have several generations each season.Almost all lace bugs live on leaf undersurfaces where they feed by removing the cell contents of several cells in any given area. This usually results in a small yellow to white spot appearing on the upper surface. Heavy feeding can cause general yellowing or blanching of host foliage.Control can be achieved by using contact pesticides, including insecticidal soaps and oils, but these need to be directed to leaf undersurfaces.Woody Ornamental Pest GroupsSucking Pests - AphidsWoody Ornamental Pest GroupsSucking Pests - Aphids•Pear-shaped insects with long antennae and diagnostic cornicles on abdomen.•Most alternate between sexual and asexual forms.•Most alternate between spring hosts (usually woody plants) and summer hosts (usually annuals or herbaceous