Slide Presentation

TITLE    (click title to view slides)
Turfgrass Weed Management II. Broadleaf Weed Control

AUTHOR
Dr. Tim R. Murphy
Extension Weed Specialist
University of Georgia
Griffin, GA

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TABLE OF CONTENTS
  1. Turfgrass Weed Management II. Broadleaf Weed Control
  2. Broadleaf Control
  3. Growth Regulator Herbicides
  4. Broadleaf Herbicides
  5. Phenoxy + Dicamba Herbicides
  6. Phenoxy + Dicamba Herbicides
  7. Phenoxy, Dicamba, Picolinic Herbicides
  8. Post Herbicide Use Guidelines
  9. Post Herbicide Use Guidelines
  10. Post Herbicide Use Guidelines
  11. Examples of Rain-Free Periods
  12. Post Herbicide Use Guidelines
  13. Post Herbicide Use Guidelines
  14. Lawn burweed
  15. Common chickweed
  16. Sticky chickweed
  17. Henbit
  18. Purple deadnettle
  19. Compare henbit and purple deadnettle
  20. Hairy bittercress
  21. Shepherd's purse
  22. Purple cudweed
  23. Parsley-piert
  24. Corn speedwell
  25. Virginia buttonweed
  26. Dandelion
  27. Wild violet
  28. White clover
  29. Spotted burclover
  30. Annual lespedeza
  31. Chamberbitter
  32. Prostrate spurge
  33. American burnweed
  34. Pennywort
  35. Dichondra
  36. Ground ivy
  37. Buckhorn plantain
  38. Blackseed plantain
  39. Woodsorrel
  40. Non-Target Plants
  41. Nonselective Control
  42. Nonselective Broadleaf Control
  43. Lack of Post Herbicide Performance
  44. Lack of Post Herbicide Performance



SLIDE CONTENTS
  1. Turfgrass Weed Management II. Broadleaf Weed Control Tim R. Murphy Crop and Soil Sciences The University of Georgia
  2. Broadleaf Control Most broadleaf control is done with postemergence herbicides. The essential broadleaf herbicides are: Postemergence - growth regulators and sulfonylureas Pre and post – atrazine, simazine, metribuzin. Pre only - Gallery
  3. Growth Regulator Herbicides
  4. Broadleaf Herbicides There are many growth regulator combinations on the market. Mixtures of broadleaf-active herbicides tend to control more weed species than each individual component herbicide.
  5. Phenoxy + Dicamba Herbicides
  6. Phenoxy + Dicamba Herbicides
  7. Phenoxy, Dicamba, Picolinic Herbicides
  8. Post Herbicide Use Guidelines Try to avoid spraying warm-season grasses during transition. Shade grasses are less herbicide tolerant than grasses growing in full sun. Spray when wind speeds are less than 5 mph.
  9. Post Herbicide Use Guidelines Avoid stress conditions (> 90 F.) Avoid spring transition on warm-seasons Repeat applications Do not mow 24 to 48 hours before or after application Rainfall and irrigation effects
  10. Post Herbicide Use Guidelines Do not water for 12-24 hours. Need a rain free period of at least 6 hours. Avoid extreme temperatures. Apply when temperatures are between 40 and 80°F.
  11. Examples of Rain-Free Periods MSMA - 24 hours Trimec Classic - 24 hours Basagran T/O - 8 hours Finale - 4 hours Vantage - 1 hour
  12. Post Herbicide Use Guidelines Annual weed control is excellent in the seedling stage and poor as the weed matures Perennial weeds are more susceptible in the Spring or Fall because root reserves are usually depleted and the weed has less recovery potential Apply to actively growing weeds - the cuticle is more easily penetrated Sprays give better control than granules.
  13. Post Herbicide Use Guidelines Repeat applications are most effective for tough perennials. Apply during good growing conditions when adequate soil moisture is present. Add a surfactant if called for on label.
  14. PPT Slide Low growing winter annual lawn burweed fruit Pre or postemergence atrazine or simazine in mid-fall. Prompt and Sencor are also effective on tolerant turfgrasses. Repeat applications of 2 or 3-way 2,4-D type herbicides. The key is applying in the fall when the weeds are small
  15. PPT Slide common chickweed winter annual
  16. PPT Slide winter annual sticky chickweed
  17. henbit winter annual Henbit
  18. PPT Slide winter annual Purple deadnettle
  19. PPT Slide henbit purple deadnettle winter annuals
  20. PPT Slide winter annual hairy bittercress
  21. PPT Slide fruit winter annual shepherd’s purse
  22. PPT Slide annual or biennial purple cudweed
  23. PPT Slide winter annual parsley-piert
  24. PPT Slide winter annual seedling corn speedwell
  25. Virginia buttonweed Difficult to control. Try digging if there are only a few plants. Repeat applications of 3-ways or 2,4-D about 4 weeks apart are needed for adequate suppression. 2,4-D seems to have the most activity.
  26. Dandelion - Perennial 2,4-D Trimec Confront Drive
  27. wild violet - perennial Triclopyr-containing formulations (Turflon, Confront) Some think dichlorprop is better on violet. Confront requires careful use in warm-season. Safe in fescue.
  28. white clover - perennial Confront, Lontrel and Manor are very effective. Warm-season grasses should be dormant or fully greened-up.. Lontrel and Manor have greater turf safety than Confront. Trimec or other 3-ways are effective. May take two applications.
  29. PPT Slide winter annual Spotted burclover
  30. PPT Slide Annual lespedeza Summer annual
  31. PPT Slide Chamberbitter, niruri Summer annual Brought to Georgia in ornamental container plants. Atrazine or simazine applied twice, 30 days apart. Prompt also works well. 2 or 3-way broadleaf mixtures applied 7 days apart are also effective in tolerant turfgrasses.
  32. prostrate spurge - summer annual Postemergence: Manor, Sencor, Trimec Preemergence: Simazine, atrazine, Gallery
  33. PPT Slide summer annual fireweed The 2 and 3-way growth regulator herbicides and Manor. Preemergence products are not very effective or provide only short term control. American burnweed (fireweed)
  34. PPT Slide Pennywort or dollarweed perennial Atrazine or simazine applied twice, 30 days apart. Prompt also works well. Image, Drive and Manor. 2- or 3-way broadleaf mixtures applied 7 days apart are also effective in tolerant turfgrasses.
  35. PPT Slide Dichondra, rhizomatous perennial Controlled by repeat applications of atrazine, 30 days apart. 2 and 3-way growth regulator herbicides. Confront is a little better than Trimec related compounds.
  36. PPT Slide perennial ground ivy
  37. PPT Slide buckhorn plantain perennial
  38. PPT Slide perennial blackseed plantain 100% Control Confront 2 pts/acre Trimec 4 pts/acre
  39. PPT Slide perennial woodsorrel (Oxalis spp.)
  40. Non-Target Plants Check for restrictions on the use of herbicides around trees and shrubs. Be very careful around vegetables and ornamentals with growth regulator herbicides. Avoid applying dicamba and atrazine under shallow rooted ornamentals such as azalea and rhododendron.
  41. Nonselective Control Roundup Pro - Do not tank mix with Reward or Finale if you are trying to control perennials. Rapid burndown prevents translocation of Roundup through the plant.
  42. Nonselective Broadleaf Control Roundup Pro - slow acting (7-14 days) but provides the best control of perennials. Reward - fastest burndown, poor perennial control, poor grass control. Finale - Almost as fast as Reward, will leave a straight edge, very good on white clover and other legumes. Not good on perennials.
  43. Lack of Post Herbicide Performance Environmental stresses Weed growth stage Rain/irrigation wash-off No adjuvant Poor spray coverage
  44. Lack of Post Herbicide Performance Wrong rate Wrong herbicide No follow-up application Mowing effects