1. Post-emergent Management Of Poa annua in Bermudagrass Turf
- New Products -
Urban Ag Council Meeting
September 23, 2014
Joe Chamberlin Ph.D.
Manager, Field Development
Valent Professional Products

3. Outline of Today’s Talk
Poa annua biology
Post-emerge Poa management
Product selection - considerations
Advantages/ limitations
Research
BHP (Best Herbicide Practices)

4. Poa annua - Biology Annual grassy weed Germination
(Some short lived perennial biotypes)
Germination
Mostly fall: September-November (80% NC)
Often not visible until spring due to turf cover
Herbicide resistance
Significant problem
Poa is one of top customer complaints

5. Product Selection - Considerations
Stage of Poa development
Turf species and dormancy
Presence of other weeds
Herbicide movement potential
Use site
Herbicide history – resistance
Cost – product, labor, call backs, retention

6. Herbicide Options – Pre-emerge
Old products
Triazines
Simazine and atrazine
Dinitroanalines (DNA)
Dithiopyr, oryzalin, pendimethalin, prodiamine
PPO
Oxadiazon (Ronstar)*

7. Herbicide Options – Pre-emerge
New products
Freehand (dimethenamid + pendimethalin)
Specticle (indaziflam)
SureGuard (flumioxazin)

9. Why post emerge? Miss preemerge application window Broadleaf weeds
Weather
Scheduling
New customer
Broadleaf weeds
Many pre-emerge herbicides not effective
Ex. Lawn burweed
Resistance
Triazines
ALS
DNAs
Escapes from pre treatment

10. Herbicide Options – Post-emerge
Old products
ALS inhibitors
Certainty, Katana*, Monument*, Revolver, Tranzit*
Finale (glufosinate)
Prograss (ethofumasate)
Roundup (glyphosate)
Kerb (pronamide)*
Triazines
Simazine, Atrazine
* Not labeled for residential turf

11. Herbicide Options – Post-emerge
New products
Specticle (indaziflam)
Very early post
SureGuard (flumioxazin)

12. Specticle

13. Specticle (indaziflam)
Advantages
Highly effective against Poa (preemerge, early post)
Controls many winter annual broadleaf weeds
Very long residual
Also effective against crab and goosegrass
New MOA – Cellulose biosynthesis inhibitor
Resistance management
Labeled for all turf use sites and landscape ornamentals
No stain or odor

14. Specticle (indaziflam)
Limitations
May interact with bermuda winter kill/ slow emergence from dormancy in shady
Limited post activity – Seedling Poa only
Potential for down slope movement
Less potential for movement than ALS, triazine or Kerb
Injurious to cool season turf
Product cost

15. Indaziflam at 35 g ai/ha Pictures: Jan. 20, 2011
October application
November application

16. Specticle BHP 6-10 fl oz/ A for Poa (Specticle Flo)
Apply August – October for optimal Poa control
Avoid application or runoff onto desirable cool season turf

17. SureGuard

18. SureGuard (flumioxazin)
Advantages
Pre and post-emergent control (8-12 oz/A)
New MOA for post control – PPO inhibitor
Wide Poa application window (November – March)
No delay in bermuda greenup if applied when dormant
Controls most winter annual broadleaf weeds
Fast post-emergent activity
Low potential for movement
Pre control of crab and goosegrass (Feb-March application)
Can tank mix with other post herbicides
No stain or odor
Labeled for all turf use sites, woody landscape ornamentals (directed), bare ground (crack/ crevice)

19. SureGuard (flumioxazin)
Limitations
Will injure actively growing bermudagrass
Accelerated dormancy in fall
No delay in greenup
Slower acting against Poa in colder weather
Product Cost

20. Data combined over trials in CA and AL
SureGuard – Annual Bluegrass Control Dormant Bermudagrass Turf – April Ratings
Poa 2+ tiller stage
Annual Bluegrass was in flower at time of March 7 application, with 30-40% cover of untreated plots. None of treatments delayed bermudagrass green-up
Data combined over trials in CA and AL

21. Untreated Control Image: Jan-18-2012

22. SureGuard 12 oz/ A – Dec. 5 Image: Jan-18-2012 (39 DAA)

23. SureGuard 12 oz/ A – Jan. 4 Image: Jan-18-2012 (14 DAA)

24. SureGuard 12 oz/ A – Dec. 7 Image: Mar-22-2011 (111 DAA)

25. SureGuard 12 oz/A - Applied March 11
Photo: March 23
SureGuard 12 oz/A - Applied March 11

26. SureGuard® Herbicide Dormant Turf
Arizona State University, Karsten Golf Course
Untreated, non-overseeded Bermudagrass rough;
all Poa annua
SureGuard treated area
Ryegrass fairway
Bermudagrass green-up
SureGuard was applied at 12 oz/A plus non-ionic surfactant 0.25% v/v on Nov. 2, 2011; picture was taken Feb. 15, Bermudagrass is coming out of dormancy in the plot area.

27. SureGuard BHP 10-12 oz/ A for Poa
Apply November- December for optimal Poa control
Tank mix with metsulfuron if perennial broadleaf weeds (ex. dandelion, clover) present
Tank mix with surfactant
Avoid application after bermuda begins active growth in spring

28. SureGuard Application Window Bermudagrass Turf
Poa and Winter Annuals germinate
Green/active
Semi-dormant
Semi-dormant
Green/active
SureGuard
Dormant 28

29. SureGuard Application Window Bermudagrass Turf
Poa and Winter Annuals germinate
Green/active
Semi-dormant
Semi-dormant
Green/active
SureGuard
Dormant
Optimal timing for Poa annua 29

30. SureGuard Application Window Bermudagrass Turf
Poa and Winter Annuals germinate
Green/active
Semi-dormant
Semi-dormant
Green/active
SureGuard
Dormant
Optimal timing for Poa
Optimal timing for Goosegrass/ Crabgrass 30

31. Questions?