Lane Tredway Summer Green Road Show Raleigh, NC August 17, 2011

1. New Tools for Turf Disease Management in
the Landscape
Lane Tredway
Associate Professor and Extension Specialist
Department of Plant Pathology
North Carolina State University

2. Turf diseases are stress-induced

3. Turf diseases are stress-induced

4. Turf diseases are stress-induced

5. Many diseases appear similar from a distance

6. Identification of the affected turf species is essential for
accurate disease diagnosis
Tall fescue
• ridged upper leaf
surface
Kentucky bluegrass
• smooth upper leaf
surface

7. Each Turf Species
Has Unique Problems
Tall Fescue
• brown patch, gray leaf spot,
Pythium blight
Kentucky bluegrass
• dollar spot, summer patch,
Pythium blight, rust,
powdery mildew

8. Symptoms: change in the appearance of the plant
Stand Symptoms
• a change in the appearance of the turf,
evident from a distance
Plant Symptoms
• a change in the appearance of the plant

9. Signs: evidence of the presence of a pathogen
mycelium sclerotia
Pythium blight red thread

14. turfpathology.org: How to follow along...
turfpathology.org
facebook.com/turfpathology
twitter.com/ncturfpathology
feeds.feedburner.com/turfpathology

15. Disease Diagnosis Utility

16. Disease Diagnosis Utility

17. Disease Diagnosis Utility

18. Disease Diagnosis Utility

19. Disease Diagnosis Utility

20. Disease Management Utility

21. Disease Management Utility

22. Disease Management Utility

23. Disease Management Utility

24. Rhizoctonia diseases are the most common and
destructive in landscape turfgrasses.
brown patch of tall fescue large patch of zoysiagrass
caused by Rhizoctonia solani caused by Rhizoctonia solani

25. QoI and DMI Fungicides for Rhizoctonia control
QoI Fungicides DMI Fungicides
Compass Bayleton
Disarm Banner
Heritage Eagle
Insignia Torque
Tourney
QoI + DMI Combinations Trinity
Armada
Disarm M
Headway

26. The QoI fungicides have revolutionized Rhizoctonia control

27. QoI Fungicides: A Growing Chemical Class
• Heritage (1996)
• Compass (1999)
• Insignia (2004)
• Disarm (2008)

28. Fungicide Prices: What do they mean?
Product Cost per lb
Heritage $ 365
Compass $ 300
Banner Maxx $289 (gal)
Bayleton $ 81
Eagle $ 73
ProStar $ 50
SysStar $ 43
3336 $ 22
ConSyst $ 12

29. Brown patch control in tall fescue, Charlotte, 2003.
Heritage (0.2 oz)
Heritage (0.1 oz)
Compass (0.25 oz)
Compass (0.15 oz)
Insignia (0.9 oz)
Insignia (0.5 oz)
Banner Maxx (2 oz)
Bayleton (1 oz)
Eagle (0.6 oz)
Untreated
0 20 40 60 80
Brown Patch Incidence (%)

30. Fungicide Recommendations for Brown Patch Control
Recommended Recommended
Product $/acre/day
Rate (/1000 ft2) Interval (days)
Disarm 0.18 fl oz 28 $5
Heritage 50WG 0.2 oz 28 $7
Heritage TL 1 fl oz 28 $7
Compass 0.2 oz 21 $10
Insignia 0.7 oz 28 $10
ProStar 2.2 oz 28 $10

31. QoI and DMI Fungicides for Rhizoctonia control
QoI Fungicides DMI Fungicides
Compass Bayleton
Disarm Banner
Heritage Eagle
Insignia Torque
Tourney
QoI + DMI Combinations Trinity
Armada
Disarm M
Headway

32. Brown patch control in tall fescue, Raleigh, 2009.
15
Heritage TL (1 oz)
Tourney (0.37 oz)
Trinity (2 oz)
Untreated
11.25
Brown Patch Incidence (%)
7.5
3.75
0
19-Jun 26-Jun 7-Jul 29-Jul 3-Aug
Treatments applied on 8 Jun, 7 Jul, and 13 Aug

33. DMI + QoI combination products control the most
important landscape diseases

34. QoI + DMI Products for Landscape Turf
Headway
azoxystrobin + propiconazole (Heritage + Banner)
Armada
trifloxystrobin + triadimefon (Compass + Bayleton)
Disarm M
fluoxastrobin + myclobutanil (Disarm + Eagle)

35. Brown patch control in tall fescue, 2004
Heritage (0.2 oz, 28 day)
Compass (0.25 oz, 28 day)
Armada (0.6 oz, 21 day)
Armada (1.2 oz, 21 day)
Armada (1.2 oz, 28 day)
Untreated
0 5 10 15 20 25 30 35 40 45
Brown Patch Incidence (%)

36. Brown patch control in tall fescue, 2006
Armada (1.2 oz)
Armada (0.6 oz)
Heritage TL (2 fl oz)
Heritage TL (1 fl oz)
Heritage TL (0.5 fl oz)
Headway (3 fl oz)
Headway (2 fl oz)
Headway (1.5 fl oz)
Headway (0.75 fl oz)
Untreated
0 3 6 9 12 15
Brown Patch Incidence (%)

37. Brown Patch Control: Combination Products
A.I.s Trade Name Rate/1000 ft2 Interval $/acre/day
trifloxystrobin
Armada 1.2 21 day $9
+ triadimefon
flutolanil +
SysStar 2.2 28 day $9
thiophanate
azoxystrobin
+ Headway 1.5 28 day $14
propiconazole

38. What about granular fungicides?

39. Comparison of granular and sprayable fungicides, Charlotte, 2003.
Systemic Fungicide G (87 oz)
3336 (4 oz)
Fungicide VII G (85 oz)
Bayleton (1 oz)
Untreated
0 20 40 60 80
Brown Patch Incidence (%)

40. Bayleton (1 oz) Fungicide VII (85 oz)

44. ???

45. Modern granular carriers are improving fungicide
performance
Heritage G
Headway G
Disarm G

46. Comparison of Granular and Sprayable Fungicides
Heritage G (3 lb)
Compass G (4 lb)
Disarm G (2.3 lb)
Heritage WG (0.2 oz)
Untreated
0 3 6 9 12 15
Brown Patch Incidence (%)
Granular treatments re-applied every 21 days, Heritage 50WG re-applied every 28 days

47. Environmental Impact Quotient (EIQ)
What’s the real environmental impact?
http://www.nysipm.cornell.edu/publications/eiq/

48. Product Rate/1000 ft2 Interval EIQ/month
Heritage 50WG 0.2 oz 28 days 7.3
Rhapsody 5 oz 7 days 7.6
Bayer Fungus
2 lbs 14 days 28
Control
Scotts Lawn
1.35 lbs 14 days 64
Fungus Control
Daconil Ultrex 3.2 oz 14 days 538

49. Kentucky bluegrass diseases are becoming more common in landscapes

50. Mixtures help to reduce brown patch injury
30.0
Coronado + Livingston
Coronado + Midnight
Brown Patch Incidence (%)
22.5
15.0
7.5
0
100:0 97.5:2.5 95:5 90:10
Mixing Ratio (% by weight)
Mixtures planted in Oct 1999
Data collected on 29 Jun 2001

51. Mixtures are by weight, not number of seeds
Tall Fescue Kentucky Bluegrass
500 seeds/gram 4,800 seeds/gram

52. Mixtures are by weight, not number of seeds
Mix Ratio Tall Fescue Kentucky Bluegrass
TF:KBG Seeds (#) Seeds (#)
90:10 204,000 218,000
95:5 216,000 109,000
97.5:2.5 221,000 54,000

53. Turfgrass populations may shift over time....
100
%TF in 1999
%TF in 2002
75
Percent Tall Fescue
50
25
0
100:0 97.5:2.5 95:5 90:10
Seed Ratio By Weight (TF:KBG)

54. Dollar spot is active when lows are above 50ºF and highs are below 90ºF

55. Summer patch is active when soil temperatures are above 65ºF

56. turfpathology.org: How to follow along...
turfpathology.org
facebook.com/turfpathology
twitter.com/ncturfpathology
feeds.feedburner.com/turfpathology