Slide Presentation

TITLE    (click title to view slides)
Diagnosing Herbicide Injury Problems

AUTHOR
Eric P. Prostko
Professor and Extension Weed Specialist
University of Georgia

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TABLE OF CONTENTS
  1. Diagnosing Herbicide Injury Problems
  2. What happens when you spray an herbicide (or any pesticide)?
  3. Potential Causes of Herbicide Injury
  4. Peanut Variety Response to Brake 1.2SL - 2019
  5. Profine/Sandea (halosulfuron) PRE on Sorghum
  6. Paraquat Drift
  7. Valor Sprayer Tank-Contamination
  8. Valor/Sprayer Clean-Out
  9. Picloram Carryover to Peanut
  10. Grazon P+D Label
  11. Herbicide Carryover
  12. Average Daily Soil Temperatures - 2020
  13. My Extension Experience (28 years)
  14. Valor Injury or Soil pH/Zn?
  15. Herbicide Injury or Nematodes???
  16. Herbicide Drift or Potassium?
  17. Herbicide Symptomology
  18. Herbicide Injury Problems Are Preventable
  19. Information You Must Collect
  20. Know Who to Contact (Your Extension Weed Science Team)
  21. Questions/Comments



SLIDE CONTENTS
  1. Diagnosing Herbicide Injury Problems Eric P. Prostko Extension Weed Specialist Dept. Crop & Soil Sciences University of Georgia Extension Agent Training March 19, 2021
  2. What happens when you spray an herbicide (or any pesticide)? Drift
  3. Potential Causes of Herbicide Injury Wrong rate/timing for crop/soil type label calibration Off-Target Movement (UPW) physical drift volatility Sprayer Contamination Carryover
  4. Peanut Variety Response to Brake 1.2SL - 2019 PE-04-19 July 7 67 DAP GA-06G GA-06G GA-18RU GA-16HO 1 = NTC 2 = 16 oz/A 3 = 32 oz/A 4 = 64 oz/A 1 2 3 4
  5. Profine/Sandea (halosulfuron) PRE on Sorghum Soil pH = 5.7 Nematodes: ring (9)
  6. Paraquat Drift
  7. Valor Sprayer Tank-Contamination
  8. Valor/Sprayer Clean-Out Spray equipment, including mixing vessels and nurse tanks, must be cleaned each day following Valor EZ Herbicide2 application. After Valor EZ Herbicide2 is applied, the following steps must be used to clean the spray equipment: 1. Completely drain the spray tank, rinse the sprayer thoroughly, including the inside and outside of the tank and all in-line screens. 2. Fill the spray tank with clean water and flush all hoses, booms, screens and nozzles. 3. Top off tank, add 1 gallon of 3% household ammonia (or equivalent) for every 100 gallons of water, circulate through sprayer for 5 minutes, and then flush all hoses, booms, screens and nozzles for a minimum of 15 minutes. If diaphragms are being used on the spray boom, loosen diaphragms before flushing the spray system, allowing cleaning solution to spray through the open diaphragm. If spray lines have any end caps, they must be loosened before flushing the system, allowing cleaning solution to spray through the loosened caps. To enhance removal of Valor EZ Herbicide2 from the spray system, add a tank cleaner for example ”Valent Tank Cleaner” from Valent U.S.A. LLC, in place of ammonia and allow the cleaning solution to remain in the pressurized spray system (spray tank, hoses and boom) overnight before flushing the system for a minimum of 15 minutes. 4. Drain tank completely. 5. Add enough clean water to the spray tank to allow all hoses, booms, screens and nozzles to be flushed for 2 minutes. 6. Remove all nozzles and screens and rinse them in clean water. Thoroughly clean spray equipment, including all tanks, hoses, booms, screens and nozzles, cleaned before it is used to apply postemergence pesticides. Equipment with Valor EZ Herbicide2 residue remaining in the system may result in crop injury to the subsequently treated crop.
  9. Picloram Carryover to Peanut
  10. Grazon P+D Label For the control of broadleaf annual and perennial weeds, and certain woody plants and vines on CRP, rangeland and permanent grass pastures. On areas treated with this product, do not rotate to crops intended for food or feed use, other than range or pasture grasses, rye, forage sorghum, sudangrass, wheat, barley or oats not underseeded with a legume. Do not move treated soil, or use treated soil for growing other plants until soil residues of picloram are no longer detectable as indicated by an adequately sensitive bioassay or chemical test. Do not use grass or hay or plant materials from treated areas or manure from animals being fed treated forage or hay for composting or mulching of desirable, susceptible broadleaf plants. Do not use manure from animals grazing treated areas on land used for growing broadleaf crops, ornamentals, orchards or other susceptible, desirable plants. Manure may contain enough picloram to cause injury to susceptible plants.
  11. Herbicide Carryover Has not been that common in GA (at least for me) Depends upon many factors crop/rate/soil texture/OM/pH/tillage/ environment much of GA is in an environment that favors the breakdown of herbicides high rainfall, low OM, lighter soils, soils never freeze
  12. Average Daily Soil Temperatures - 2020 Source: UGA Weather Network Tifton (Optimum soil temperatures for microbial activity are 60-85° F)
  13. My Extension Experience (28 years) Many, not all, herbicide injury complaints turn out to be something else. low soil pH nematodes soil compaction Keep a soil/nematode/compaction probe and plastic bags in your truck at all times. Standard soil testing and grid sampling can often miss hot spots.
  14. Valor Injury or Soil pH/Zn? July 2007 pH = 5.04 Zn = 14-17 lbs/a
  15. Herbicide Injury or Nematodes??? 796-Rootknot nematodes/sample 50+ is a problem
  16. Herbicide Drift or Potassium? Soybeans are a BIG user of potash (1.14 lbs K20 removed/bushel)
  17. Herbicide Symptomology First and foremost, I am available 24/7 if you need me (229-392-1034) Purdue University https://www.btny.purdue.edu/Extension/Weeds/HerbInj2/InjuryHerb1.html University of California http://herbicidesymptoms.ipm.ucanr.edu/?src=sub University of Florida Cotton (https://edis.ifas.ufl.edu/pdffiles/AG/AG36700.pdf) Corn (https://edis.ifas.ufl.edu/pdffiles/AG/AG37400.pdf) Peanut (https://edis.ifas.ufl.edu/pdffiles/AG/AG33700.pdf) Texas A&M University Peanut (http://publication.tamu.edu/PEANUTS/PUB_peanuts_Peanut%20Herbicide%20Injury%20Symptomology%20Guide.pdf) Montana State University https://msuextension.org/pubs/herbicideinjuryguide/index.html Australia Dept. of Primary Industries Cotton (https://cotton.ces.ncsu.edu/wp-content/uploads/2015/07/CRC-Herbicide-Symptoms.pdf?fwd=no) Oregon State University Grapes (https://catalog.extension.oregonstate.edu/sites/catalog/files/project/pdf/em8860.pdf)
  18. Herbicide Injury Problems Are Preventable Read/follow label Use right rate for soil type Calibrate sprayer Follow labeled crop rotation restrictions Proper sprayer cleanout Rush and flush don’t cut it Avoid off-target movement (UPW) situational awareness, wind speed/direction, nozzle type, boom height, speed, pressure, etc. Do not put herbicides in unlabeled containers
  19. Information You Must Collect At the very least … Last year’s crop Last year’s pesticides This year’s crop and variety This year’s pesticides applied Last pesticide in sprayer Neighboring crops Your awesome if you have… Soil Test Results Nematode Results
  20. Know Who to Contact (Your Extension Weed Science Team) Eric Prostko Peanuts, soybeans, field corn, sunflowers, grain sorghum, sesame, canola, field pea Mark Czarnota Ornamentals, small fruits, nursery, landscape, greenhouse, Christmas Trees Stanley Culpepper Cotton, small grains, vegetable crops (including sweet corn) Patrick McCullough Turf Forages Pastures Right of Way Non-crop Gary Burtle Ponds/Aquatics Wayne Mitchem Tree fruits (NCSU) Lisa Baxter Forages
  21. Questions/Comments Slide set is available at gaweed.com