Ornamental Pest Management (Category 3B)

1. Ornamental Pest Management (Category 3B) Biology and Management of Pests Chapter 6

2. A “stab in the dark” approach to pest management is seldom effective. It may injure desirable organisms.

3. Effective Pest Management • Requires... • Knowledge of pest life cycle • Feeding habits • Hosts • Environmental interaction • Reproductive behavior

4. Diseases of Ornamentals • Disease = disturbance of normal plant function. • Noninfectious (abiotic) • Environmental • Cultural practices • Infectious • Fungi • Bacteria • Virus

5. Apple Scab Life Cycle Summer Spring leaf to leaf infection spores blown to new leaves infected leaves fall Winter fungus overwinters on fallen leaves

6. Plant Diseases • Grouped according to: • Causal agent • Symptoms they produce

7. Leaf spots Scab Rusts Powdery mildew Mosaics Chlorosis Scorch Witches’ broom Disease Symptoms

8. Anthracnose Cankers Blights Wilts Decline Galls Rots Disease Symptoms

9. Scab

10. Rust

11. Cedar-Apple Rust Cedar-Hawthorne Rust

12. Powdery Mildew

13. Mosaic

14. Chlorosis: Oak and Maple

15. Witch’s broom caused by Anthracnose

16. Anthracnose on foliage and in woody tissue.

17. Fireblight on Mountain Ash

18. Root rot problem on Rhododendron

19. Common symptom of tree decline.

21. Host Susceptibility • Plant selection • Plant parts • Vigor

22. Weather Conditions • Humidity • Rainfall • Temperature

23. Microclimate • Shade • Wind • Salt • Location • Crowding

24. Infectious Disease Management • Resistance • Superior species, cultivars, varieties • Avoidance • Appropriate site conditions • Elimination • Sanitation; some fungicides • Protection • Most fungicides

25. Although cultural and environmental disorders are most common, “bugs” are perceived as the likely cause of a problem.

26. Insects of Ornamentals • Capable of wide variety of injury • May go through several life stages • Activity and injury often seasonal • Classified by physical characteristics • Classified by behavior

27. Insect Classification by Feeding Behavior • Piercing - sucking • Leaf-chewing • Tent and case-making • Gall-forming • Root-feeding • Boring

28. Piercing-sucking Insects • Aphids • Leafhoppers • Plant bugs • Mealybugs • Thrips

29. Piercing-sucking Insects Aphids

30. Piercing-sucking Insects Pine Needle Scale

31. Piercing-sucking Insects Magnolia Scale

32. Piercing-sucking Insects Sooty mold grows on the honey dew secreted from piercing-sucking insects.

33. Piercing-sucking Insects Plant Bug

34. Piercing-sucking Insects Leaf Hopper Injury

35. Leaf-Chewing Insects • Caterpillars • Sawflies • Leafminers • Leaf beetles • Weevils

36. Leaf-Chewing Insects Eastern Tent Caterpillar

37. Leaf-Chewing Insects Pine Sawfly

38. Leaf-Chewing Insects Birch Leaf Miner (sawfly) Oak leaf miner (moth)

39. Leaf-Chewing Insects Japanese Beetle

40. Leaf-Chewing Insects Black Vine Weevil: Adult, pupae, larvae (legless), and foliar damage

41. Leaf-Chewing Insects White grub of Japanese beetle: a root feeder.

42. Maple Bladder Gall

43. Cooley Spruce Gall

44. Bronze Birch Borer exit hole

45. Insect Management • Protection for insects: • Pupal stage • Waxy coating • Galls • Bark • Leaf tissue • Soil

46. Susceptible life stage Damaging stage Period of feeding Weather conditions Number of generations Host tolerance Natural enemies Insect Management- Consider:

47. Non-Chemical Insect Controls • Improve plant vigor • Encourage natural enemies • Select plants with resistance • Modify the environment

48. Natural enemies of insects can provide safe, long lasting “control.” Pesticides can upset this balance and increase some problems.

49. Insecticides • Avoid problems: • Monitor plants for insects • Protect beneficials • Time for appropriate life stage • Avoid preventative pesticide treatments • Use the least toxic materials

50. Mites • Not insects (eight legs) • Rasp leaf cells and suck contents • Causes bronzing • Some form webs or galls • Weather dependent - prefer hot spots • Rapid population build up • Paper test