Weed%20Management%20on%20Putting%20Greens

1
Weed Management on Putting Greens

• Dr. Tim R. Murphy
• Extension Weed Specialist
• University of Georgia
• Griffin

2
Problem Putting Green Weeds

• Annual Bluegrass - annual and perennial
• Goosegrass
• Crabgrass
• occasional broadleaf weeds
• nutsedge(s)

3
Bermudagrass Greens

• Preemergence crabgrass and goosegrass
• Bensulide (Bensumec, Pre-San, Betasan
• Dithiopyr (Dimension)
• Bensulide oxadiazon (Scotts Goosegrass/Crabgrass
  Control)

4
Bermudagrass Greens

• Postemergence crabgrass and goosegrass
• Diclofop (Illoxan), goosegrass only
• MSMA/DSMA - low rates, repeat applications, very
  risky, avoid air temperatures gt 85 F.

5
Bermudagrass Greens

• Preemergence annual bluegrass control
• Pronamide (Kerb) , apply 60 to 90 days before
  overseeding, activated charcoal is used when
  applications made lt 90 days before overseeding
• Fenarimol (Rubigan), apply 2 to 3 applications,
  last application 14 days before overseeding
  perennial ryegrass (30 days on P. trivialis),
  apply low rate in Jan.-Feb, for extended control

6
Creeping Bentgrass Greens

• Preemergence crabgrass and goosegrass
• Bensulide (Bensumec, Pre-San, Betasan
• Dithiopyr (Dimension)
• Bensulide oxadiazon (Scotts Goosegrass/Crabgrass
  Control)

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Creeping Bentgrass Greens

• Postemergence crabgrass and goosegrass
• No herbicides labeled for this use
• Low tolerance of creeping bentgrass
• MSMA/DSMA - very risky
• Acclaim Extra - too injurious

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Creeping Bentgrass Greens

• Annual bluegrass control
• Paclobutrazol (Scotts TGR, Trimmit)
• a plant growth regulator that inhibits
  gibberellin biosynthesis
• Poa more sensitive than bentgrass
• apply in spring after bentgrass growth has
  resumed
• works slowly, repeat applications needed
• fall spring applications needed for P. annua
  var. reptans

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Perennial Poa Treatments (Johnson and Murphy,
1995)

• TGR applied Oct. 1 Nov 12 fb Mar 15 May 1 for
  2 yr suppressed Poa 28 4 MAT
• TGR at 0.5 0.25 fb 0.5 0.25 lbs. Ai/acre
• Cutless at same dates and rates suppressed Poa 6
  4 MAT

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Perennial Poa Treatments (Johnson and Murphy,
1996)
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Perennial Poa Suppression
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Maximum Bentgrass Injury