• Share
  • Email
  • Embed
  • Like
  • Save
  • Private Content
Ralph Whitesides Pesticides And Ornamentals Handout
 

Ralph Whitesides Pesticides And Ornamentals Handout

on

  • 662 views

 

Statistics

Views

Total Views
662
Views on SlideShare
661
Embed Views
1

Actions

Likes
0
Downloads
0
Comments
0

1 Embed 1

http://www.slideshare.net 1

Accessibility

Categories

Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

    Ralph Whitesides Pesticides And Ornamentals Handout Ralph Whitesides Pesticides And Ornamentals Handout Presentation Transcript

    • Using Pre-emergence Herbicides Effectively – Herbicide misuse Issues in the Landscape Ralph E. Whitesides Extension Weed Specialist Utah State University
    • What is a pre-emergence herbicide?
      • Herbicide applied after crop is planted but before the weeds emerge
      • Does not work on established perennial weeds or crops
      • Requires rainfall or irrigation to activate the herbicide
    •  
    • Timing is Everything!
      • Herbicide on ground & activated prior to weed seed germination
      • Spray applications of pre-emergent herbicides applied in the rain
      • Irrigation required if no rainfall
    •  
    • Getting it Right!
      • Crabgrass in turf pre-emergence control indicators
      • Some use forsythia bloom
      • Too early – should be forsythia petal fall
      • Too early run the risk of “break through”
    •  
    •  
    • Getting it Right! (continued)
      • Soil temperature – upper half inch of soil – early in day, not in sun, measure the site you intend to treat
      • Temperature above 50 °F three consecutive days make application!
      • Make split-applications if necessary
      • First part of split earlier than a single application – second treatment 7-8 weeks later
    • Environmental Effects
      • Pre-emergence at right time & activated usually very good to excellent control
      • Must be threshold level of herbicide in soil to be effective
      • Abnormally high rainfall could dilute below threshold level – sandy soil is constant problem – consider split applications
    • In Combination
      • Fertilizer carrier
      • Herbicide rate is fixed to fertilizer rate
      • Sprayed versus spreader delivered
      • Both do a good job if applied in time and activated
    • Target Practice
      • Target weed – annual bluegrass
      • Winter annual – germinates in late summer/early fall
      • Apply mid-August if germination in September
      • Soil temperature – does not germinate until soil is consistently below 70 °F
      • Can’t control perennial annual bluegrass
    • Gallery (isoxaben) Controls Perennial Broadleaves
      • Used for keeping dandelion and clover from re-invading turf
      • Necessary to control existing perennial first
    • What could cause a pre-emergence herbicide to fail?
      • 1. You failed to read the label
      • 2. You disrupted the chemical barrier
      • 3. Your herbicide combination (or lack thereof) did not cover a broad weed spectrum
      • 4. You failed to incorporate the herbicide with irrigation
      • 5. You routinely over-watered your plants
    •  
    • What are 10 reasons that pre-emergence herbicides fail?
      • 1. You failed to read the label
      • 2. You disrupted the chemical barrier
      • 3. Your herbicide combination (or lack thereof) did not cover a broad weed spectrum
      • 4. You failed to incorporate the herbicide with irrigation
      • 5. You routinely over-watered your plants
    •  
    • What are 10 reasons that pre-emergence herbicides fail?
      • 1. You failed to read the label
      • 2. You disrupted the chemical barrier
      • 3. Your herbicide combination (or lack thereof) did not cover a broad weed spectrum
      • 4. You failed to incorporate the herbicide with irrigation
      • 5. You routinely over-watered your plants
    •  
    • What are 10 reasons that pre-emergence herbicides fail?
      • 1. You failed to read the label
      • 2. You disrupted the chemical barrier
      • 3. Your herbicide combination (or lack thereof) did not cover a broad weed spectrum
      • 4. You failed to incorporate the herbicide with irrigation
      • 5. You routinely over-watered your plants
    •  
    •  
    • What are 10 reasons that pre-emergence herbicides fail?
      • 1. You failed to read the label
      • 2. You disrupted the chemical barrier
      • 3. Your herbicide combination (or lack thereof) did not cover a broad weed spectrum
      • 4. You failed to incorporate the herbicide with irrigation
      • 5. You routinely over-watered your plants
    •  
      • 6. You tried to save a few pennies by using a lower herbicide rate
      • 7. You failed to use proper sanitation
      • 8. You topdressed fertilizers
      • 9. You did not calibrate your equipment
      • 10. You applied herbicides to soil/containers that already had weeds
    •  
      • 6. You tried to save a few pennies by using a lower herbicide rate
      • 7. You failed to use proper sanitation
      • 8. You topdressed fertilizers
      • 9. You did not calibrate your equipment
      • 10. You applied herbicides to soil/containers that already had weeds
    •  
      • 6. You tried to save a few pennies by using a lower herbicide rate
      • 7. You failed to use proper sanitation
      • 8. You topdressed fertilizers
      • 9. You did not calibrate your equipment
      • 10. You applied herbicides to soil/containers that already had weeds
    •  
      • 6. You tried to save a few pennies by using a lower herbicide rate
      • 7. You failed to use proper sanitation
      • 8. You topdressed fertilizers
      • 9. You did not calibrate your equipment
      • 10. You applied herbicides to soil/containers that already had weeds
    •  
      • 6. You tried to save a few pennies by using a lower herbicide rate
      • 7. You failed to use proper sanitation
      • 8. You topdressed fertilizers
      • 9. You did not calibrate your equipment
      • 10. You applied herbicides to soil/containers that already had weeds
    •  
    • Are there cases of herbicide misuse in the landscape?
      • 2009 example – provided with home owner approval
      • Homeowner had 5 London Plane (sycamore) trees
      • Fairly large caliper trees when planted
      • Now 12 years old
      • Trees 1, 3, and 5 were being encroached upon by trees 2 and 4
      • Decided to remove the trees on May 6, 2009
      • Cut the trees down with chain saw, removed the stumps and limbs
    •  
    • Bad Decisions
      • After trees were removed
      • Father-in-law says these will sucker and make a mess of the yard
      • We better treat the stumps!
      • I have just the stuff
      • Returns with container of Tordon 22K
      • Treats stumps with straight material using a brush
      • 13 days latter the call came to USU
    •  
    •  
    •  
      • What did the yard look like in the beginning?
    •  
    •  
    •  
      • What do you tell the homeowner now?
    • Some Important Facts
      • Sycamore trees don’t sucker
      • Sycamore trees do root-graft
      • Tordon 22K is highly mobile in plants
      • Dow says the product likely moved into adjacent trees within 3-5 hours of original treatment
      • Separate the trees
      • Picloram can leak out of trees into soil
      • Remove soil and cut roots, remove stumps
    •  
    •  
      • What will happen to the trees that were not cut down?
      • Three months later
    •  
    •  
    •  
    •  
    •  
    •  
      • Seven months later
    •  
    •  
    •  
      • When can I replant some trees?
    •  
    •  
    • Picloram Persistence
      • Average field half-life is 90 days
      • Half-life range is 20-300 days
      • Dissipates more rapidly in warm moist conditions of the south
      • If half-life is 300 days it may take more than 3-5 years before it would be safe to replant deciduous trees
      • Highly leachable in some situations
      • How does this impact my neighbors?
    •  
    •  
    •  
      • Read the Label
      • Follow label instructions
        • There is a reason why some pesticides are Restricted in Use – this example is one of them