1. Turfgrass Diseases

2. Turfgrass Disease Disease: normal development disturbed; reduces value

3. Turfgrass Disease Symptom: visible reaction to a disease

4. Turfgrass Disease Abiotic: non-living causes

5. Turfgrass Disease Abiotic: Herbicide

6. Turfgrass Disease Abiotic: Scalping

7. Turfgrass Disease Abiotic: Dull Mower

8. Turfgrass Disease Abiotic: Nutrient

9. Turfgrass Disease Abiotic: Fertilizer

10. Turfgrass Disease Abiotic: Cold

12. Turfgrass Disease Biotic: living organisms, infectious Fungus…

13. Environment Temperature Fungus in the host unnoticed until the host is under stress

14. Environment Moisture Rain Dew Irrigation Poor drainage is critical

15. CULTURAL CONTROL DRAINAGE! Most important

16. CULTURAL CONTROL Disease-resistant turf Correct species or resistant cultivar

17. CULTURAL CONTROL Diversify the genetic resistance Blends: mixing cultivars of a species Mixes: mixing species of turf

18. CULTURAL CONTROL Proper turfgrass establishment At least 6” of topsoil Properly graded with good drainage

19. CULTURAL CONTROL Mowing Mow within correct height Good cut

20. CULTURAL CONTROL Irrigation Avoid irrigating in the evening Early morning to knock off the dew Deeply and infrequently

21. CULTURAL CONTROL Nutritional status Influences diseases Excessive N favors Pythium and Brown Patch

22. CULTURAL CONTROL Nutritional status Deficient N favors Dollar Spot and Rust

23. CULTURAL CONTROL Nutritional status Potassium helps environmental stress Use K in a the same proportions as N

24. CULTURAL CONTROL Thatch control Thatch can support some diseases

25. BIOLOGICAL CONTROL None used commercial with great success

26. FUNGICIDE Preventative: applied prior to favorable conditions at lower rates Curative: applied after symptoms have occurred at higher rates

27. FUNGICIDE Contacts: form preventative coating

28. FUNGICIDE Contacts New leaves have no protection Fungicide degrades under irrigation, sunlight, mowing Effective for 7 to 14 days

29. FUNGICIDE Contacts Broad spectrum controls mostly foliar diseases and not root/crown diseases

30. FUNGICIDE Penetrant Protective and curative Effective for 15 to 30 days

31. FUNGICIDE Penetrant Specific MOA, develops resistant strains Some chemicals are mixes to take advantage of both the contact and systemic effects

32. Brown Patch Causal Agent: Rhizoctonia

33. Brown Patch Hosts: zoysia, St. Augustine, centipede

34. Brown Patch Favorable Conditions: Spring and fall months Start watching in August

35. Brown Patch Symptoms: Smoke ring on greens No leaf spots, leaf sheath rot at base

36. Brown Patch Symptoms: Shoots pull off from stolons easily Roots not affected

37. Brown Patch Controls: Avoid excess N Improve drainage

38. Gray Leaf Spot Host: St. Augustine

39. Gray Leaf Spot Favorable Conditions: Mid-July Shade

40. Gray Leaf Spot Symptoms: All aboveground plant parts

41. Gray Leaf Spot Control: Collect clippings Raise mowing height

42. Dollar Spot Host: bermuda, zoysia

43. Dollar Spot Favorable Conditions: Warm weather, 60 to 80 F Low N Thatch

44. Dollar Spot Symptoms: Leaf lesions band across leaf with purple border

45. Dollar Spot Symptoms: White patches in dew fungus

48. Dollar Spot Control: Apply N

49. Dollar Spot Control: Apply N

50. Fairy Rings Causal Agent: fungi

51. Fairy Rings Favorable Conditions: Soils with high OM Frequently old tree stumps

52. Fairy Rings Symptoms: Rings with dark green on the outside Decomposition of OM and free N

53. Fairy Rings Symptoms: Decline in the middle Nutrient depletion Hydrophobic soil (dry)

54. Fairy Rings Control: Mask with N application Aerify to improve water penetration No fungicide control

56. Centipede decline Favorable Conditions Late frost in spring Fluctuating winter/spring temps Excessive N, Thatch and low K

57. Centipede decline Symptoms Die after spring green Wilts and suddenly die

58. Centipede decline Control Avoid early fertilization Avoid over fertilization Apply adequate K in fall and spring

59. Centipede decline Control Avoid post-emergents during transition Maintain pH

60. Take-All Root Rot

63. Soil pH Some reports suggests lowering pH will help Others suggest compost topdressing Fungicides not effective

64. LOCALIZED DRY SPOT Sandy soils get hydrophobic Apply wetting agent

65. SLIME MOLD Harmless