1. To Mix or Not to Mix: That is the Question? (Tank-mixing Herbicides and Fungicides) Eric P. Prostko Extension Weed Specialist Department of Crop & Soil Sciences University of Georgia

2. Why tank-mix agrochemicals? Advantages – Increase spectrum of control – decrease time and labor cost – less vine damage – decrease soil compaction Disadvantages –Reduced control –Increased crop injury –Physical incompatibility –different spray volumes/nozzle types –adjuvant recommendations

3. Spray Volumes and Nozzle Tips What is the best water volume to use for …….. –fungicides –herbicides What is the best nozzle to use for…. –fungicides –herbicides

4. Nozzle Tips Nozzle Tip HerbicidesFungicides ContactSystemicContactSystemic AIGEGE Turbo Teejet VG XR Flat Fan EGEG Turbo Floodjet NRVGNRVG Whirl rain cone VG EE Hollow cone NRGVG

5. What happens when you mix chemicals? additive * 1 + 1 = 2 synergistic * 1 + 1 = 3 antagonistic * 1 + 1 = 1 or less

6. Antagonism Gramoxone Max 8 ozs/A Gramoxone Max 10 ozs/A + Storm (1.5 pt/A) 1 DAT

7. What do the labels tell us? In most cases, not very much Unclear, vague, and confusing Trial and error Has someone else done it?

8. Cadre Tank-Mixes

9. Headline MONCUT 70DF ECHO® 720 AG PropiMax* EC Nichino America ARTISAN

10. What have we learned? Generally no major problems but….. Impossible to test under all environmental scenarios There are some specific problems

11. Annual Grasses and Select (Jordan et al. 2003. Peanut Science 30:1-7) More of a problem when applied in 25 GPA than if applied in 10 GPA % of comparisons where control was reduced –Kocide, ManKocide, Tenn-Cop = 80% 7-75% reductions in control –Bravo and others = 69% 2-60% reductions in control –Abound = 60% 5-13% reductions in control –Folicur and Tilt did not reduce efficacy

12. Texas panicum control with Cadre/fungicide tank-mixes, 2002 (67 DAT). LSD 0.05 = 20 LSD 0.10 = 17

13. A New Publication (For more specifics) Tank Mixing Chemicals Applied to Peanut Crops: Are the chemicals compatible? June 2004 Regional publication housed at NCSU (AGW-653) Available on-line at: http://www.peanut.ncsu. edu/ag653.pdf

14. New POST Labels for 2005 Strongarm –24c label in GA –No fungicide tank-mix information Cobra –Label says do not tank-mix

15. Before spraying….. Read label Water volume compatible for both Nozzle type Contact county agent Check for physical compatibility –Jar test

16. Mixing Order some water (1/2) + agitation water soluble packets wettable powder in slurry DF or WDG liquid flowables EC NIS/COC/AMS/UAN Remaining water (AMS then glyphosate)

17. Two-Jar Test 1 pt of carrier (water) to each of 2 qt jars ¼ teaspoon of compatibility agent to 1 jar –Blendex (Helena) –Mix (Drexel) –Unite (Loveland) To each jar, add required amount of pesticide in order suggested previously. Shake well after each addition. After all have been added, shake for 15 seconds and let stand for 30 minutes

18. Other issues Adjuvants –How is fungicide formulated? –How bad are the weeds? What about ….. – insecticides – fertilizer – 3 or 4 way mixes

19. www.gaweed.com