Institute for Ag Professionals

Transcription

1 Institute for Ag Professionals Proceedings of the 2010 Crop Pest Management Shortcourse & Minnesota Crop Production Retailers Association Trade Show Do not reproduce or redistribute without the written consent of author(s).

2 Ponderings, Pontifications, and Prognostications on Adjuvants Rich Zollinger North Dakota State University

3 Illuminated and ellucidated the term Optimization Dr. John Nalewaja Professor Emeratis NDSU

4 25 Commandments for glyphosate ND Weed Guide 1. Use the correct rate 2. Reducing glyphosate rates may increase resistant weed biotypes 3. Apply to small actively growing plants 4. Delay tillage 1 day for annual and 3 days for perennial weeds 5. Use the lowest water volume allowed 6. Glyphosate is highly water soluble and greatly affected by humidity 7. Oil adjuvants antagonize glyphosate 8. ALWAYS add NIS to glyphosate 8. Always add NIS to glyphosate 9. Hard water antagionizes glyphosate 10.Always add AMS to glyphosate at 4 to 6 lbs/100 gal or more for hard water 11. Contact herbicides may antagonize glyphosate 12. Cold weather may delay or reduce weed control 13. Dew on leaves may reduce weed control 14. Apply glyphosate from 8 am to 8 pm 15. Use drift management techniques 16. Glyphosate will kill plants after frost if leaf tissue is not desiccated 17. Dust inactivates glyphosate 18. Do not apply formulations that includes surfactant to bodies of water 19. Glyphosate may inhibit uptake of Mn and possibly other micronutrient 20. Delay 2 nd sequential application at least 10 days after 1 st

5 MSDS..specific chemical identity withheld.because it is a trade secret of Monsanto Company

6 RU WeatherMax = No surfactant use information RU PowerMax Partial Load 3 lb ae/gal Full Load 3 lb ae/gal

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8 Surface tension droplets on leaf surface

9 Other factors affecting absorption: Glyphosate at 1x rate = $3.00/A How much of $3.00 gets into the plant? High herbicide absorption

10 Other factors affecting absorption: Scientific journal publication review: - >25 species - Range = 3-47% - Average = 20-35% - $1 gets into the plant Remember when RU was $60/gal?

11 Conclusion Surfactant recommendations: 1. Glyt labels + MSDS do not contain information to optimize activity 2. Many weeds require additional NIS 3. Formulation NIS No load Partial load Full load 0.5 to 1% v/v 0.25 to 0.5% v/v 0.25% v/v

12 25 Commandments for glyphosate ND Weed Guide 1. Use the correct rate 2. Reducing glyphosate rates may increase resistant weed biotypes 3. Apply to small actively growing plants 4. Delay tillage 1 day for annual and 3 days for perennial weeds 5. Use the lowest water volume allowed 6. Glyphosate is highly water soluble and greatly affected by humidity 7. Oil adjuvants antagonize glyphosate 7. Oil adjuvants antagonize glyphosate 8. Always add NIS to glyphosate 9. Hard water antagionizes glyphosate 10.Always add AMS to glyphosate at 4 to 6 lbs/100 gal or more for hard water 11. Contact herbicides may antagonize glyphosate 12. Cold weather may delay or reduce weed control 13. Dew on leaves may reduce weed control 14. Apply glyphosate from 8 am to 8 pm 15. Use drift management techniques 16. Glyphosate will kill plants after frost if leaf tissue is not desiccated 17. Dust inactivates glyphosate 18. Do not apply formulations that includes surfactant to bodies of water 19. Glyphosate may inhibit uptake of Mn and possibly other micronutrient 20. Delay 2 nd sequential application at least 10 days after 1 st

13 Glyphosate tank-mixes Glyphosate #1 Soybean Weed in NC Region

14 Conundrum with adjuvant selection! Popular tank-mixes with glyphosate Glyphosate + 1. Select/generics (clethodim) 2. Status 3. Laudis/Impact/Callisto 4. Sharpen 5. Flexstar

15 Oil adjuvant antagonism of glyphosate NDSU, 2008, 28 DAT Herbicide* RR soy Flax Grass** % control Glyt+Laudis NIS NIS + AMS PO PO + AMS LSD (5%) * Glyt = 0.28 lb ae/a, Laudis = 1 fl oz/a ** Grass = averaged over oat, foxtail millet, and foxtail barley

16 ND Weed Control Guide

17 ASTM Adjuvant Defintions Crop oil concentrate (PO) = emulsifiable petroleum oil-based products containing 15-20% surfactant and remainder phytobland oil. High surfactant oil conc. (HSOC) = emulsifiable oil (PO or MSO) based products containing 20-50% surfactant and a minimum of 50% oil.

18 Ave of 6 HSOC PO based oil HSOC = enhance oil soluble herbicide not antagonize glyt. Broadleaf species No adj. = 18% Ave of 3 BL species NIS NIS + AMS LSD (0.05) = 7 (2 pt/a) - AMS + AMS Convential corn HSOC (1 pt/a) No adj. = 33% (2 pt/a) - AMS + AMS NIS NIS + AMS - AMS + AMS LSD (0.05) = 6 HSOC (1 pt/a) - AMS + AMS Control (%)

19 HSOC - MSO based oil HSOC = enhance oil soluble herbicide not antagonize glyt. Broadleaf species No adj. = 18% Ave of 3 BL species NIS NIS + AMS LSD (0.05) = 7 (2 pt/a) - AMS + AMS Convential corn HSOC (1 pt/a) No adj. = 33% (2 pt/a) - AMS + AMS NIS NIS + AMS - AMS + AMS LSD (0.05) = 6 HSOC (1 pt/a) - AMS + AMS Control (%)

20 Oil adjuvants Oil adjuvants with Glyt + Laudis (Flax and 4 broadleaf species (ave) Glyt + Laud + PO-1-2 MSO + OS MSO-1-2 PO-HSOC-1-2 MSO-HSOC lb ae + 1 fl oz 1 qt/a 1 qt/a 0.75% v/v 1.25 pt/a 1.25 pt/a 1 pt/a 1 pt/a 1 pt/a 1 pt/a 1 pt/a 0.5 pt/a COC / PO MSO+OS MSO PO-HSOC = Flax = Ave 4 species: (amar, colq, tabw, conv. soy) MSO-HSOC MSO+NIS LSD (0.05) = 5 Zollinger, % control

21 Conclusion Tank-mixtures: 1. Problem: Water-soluble glyt with oil soluble T/M partners Adjuvant selection: 1. HSOC good concept - Problem with efficacy PO HSOC = not fit definition MSO HSOC = fits definition

22 One BIG problem! Oil adjuvant rates: Conclusion Label rates Grower rates PO/COC 2 pt/a? PO-HSOC 1 pt/a? MSO 1.5 pt/a? MSO-HSOC pt/a?

23 One BIG problem! Oil adjuvant rates: Conclusion Label rates Grower rates PO/COC 2 pt/a 1% v/v PO-HSOC 1 pt/a 0.5% v/v MSO 1.5 pt/a 1% v/v MSO-HSOC pt/a 0.5% v/v

24 #8 Oil Adjuvant Rate Volume versus Area? Which concept do you use?

25 Oil adjuvant recommendations Herbicide Oil 28% AMS -v/v- - v/v - /100 gal Raptor (BASF) 1-2% 2.5% lb Assure II (Dupont) 1% 2 qt/a 2 lb/a FirstRate (Dow) 1.2% 2.5% lb Valor (Valent) qt/a lb/a Impact (Amvac) 1-1.5% % lb Callisto (Syngenta) 1% 2.5% 8.5 lb

26 Oil adjuvant recommendations Herbicide Oil 28% AMS -v/v- - v/v - /100 gal Select (Arysta/Valent) 1% or 1qt 1-2 qt/a lb/a >1 pt/a Laudis (Bayer) 1% but >1.25 pt/a 1.5 qt/a 1.5 lb/a Status (BASF) 1-2 pt/a 1.25% 5-17 lb Sharpen (BASF) 1%...1 pt/a % lb

27 2010 Extension Specialist Survey Spray volume used (gpa): State University Grower ND SD NE KS 15 5 to 10 MN to15 WI 15 to MI to 15 Ontario to 15 IA 20 8 to 15 IL to 15 IN to 15 TX 20 8 to 10

28 Oil concentration with Option (Ramsdale, NDSU, 2001) MSO MSO + UAN Spray vol. 1% v/v 1.5 pt/a 1.5 pt + 2 pt (gpa) % control (0.2 pt/a) (0.4 pt/a) (0.8 pt/a) (1.6 pt/a) LSD (0.05) (Ave of 4 species x 2 studies) 2.5 / 5 gpa = nozzle, 10 / 20 = nozzles; 20 psi

29 Oat control from Accent (Nalewaja, NDSU) NIS+ MSO Spray vol. AMS 1% v/v 1.6 pt/a (gpa) % control LSD (0.05) , 10, 20 gpa = 8001, 8004, 8004 nozzles

30 Oil volume with Laudis (Zollinger, 2008) MSO Spray vol. 1% v/v 1.5 pt/a (gpa) % control (Ave of 4 species) 8.5 (0.7 pt/a) (1.4 pt/a) LSD (0.05)

31 Petrol. Oil PO - HSOC Sharpen with oil volume, Zollinger, 2010 Ave of 4 broadleaf species 0.34 pt/a 0.7 pt/a 0.5% 0.25% 1% 0.5% = 8.5 gpa = 17 gpa 1.4 pt/a 2 pt/a 0.34 pt/a 0.7 pt/a 1.4 pt/a 2 pt/a 2% 1% 3% 1.5% 0.5% 0.25% 1% 0.5% 2% 1% 3% 1.5% % control

32 General rule: Apply oil adjuvants at 1% v/v but not less than 1.25 pt/a.

33 Drift Reduction Technology (DRT) Open comment period ends March 5, 2010.

34 Ag Buffer Zone Distances Buffer Zones 25 foot buffer for groundboom, overhead chemigation or airblast 150 feet for Non-ULV aerial applications 450 for ULV aerial applications These are Do Not Apply zones

35 Implementation of DRT Phenoxy herbicides targeted next! 250 ft

36 Sharpen What is the buffer distance mandated on the Sharpen label?

37 100 ft

38 Buffer zones Question POST-DRT A 300 ft buffer zone is what % a ¼ section of land? 300 ft ¼ Section (160 A) ½ mile ½ mile A. 10% B. 20% C. 30% D. 40% Shelterbelt

39 Can buffer distance be reduced or eliminated? Star rating determines buffer distance around each field!

40 Example of DRT Language

41 Droplet size! How do you get bigger droplet size?

42 Droplet size! Something has NOT been considered in this DRT discombobulation?

43 Weed control efficacy! Does droplet size affect weed control?

44 Lets look at data 7 Herbicides 1. Glyphosate 2. 2,4-D 3. Poast 4. Accent 5. Pursuit 6. Laudis 7. Ignite

45 Glyphosate with spray volumes NDSU, Zollinger (2009) Droplet Average Size* 4 brdlf species 2 grass species % control Fine Medium Coarse Very Coarse LSD *80 L/ha

46 Adjuvant Mode of Action #1 Pingpong balls Basketballs Volleyballs

47 Ignite with spray volumes NDSU, Zollinger (2009) Water Average Nozzle volume 4 brdlf 2 grass L/ha % control LSD

48 Label directions on droplet size Phenoxy herbicide label language:

49 28 days after application of phenoxy type herbicide Very coarse vs. Fine

50 Some DRT conclusions Consideration: 1. Extending university research to grower Do university weed scientists use same droplet size and spray quality as applicators? **Weed ratings in state weed guides**

51 Some DRT conclusions Consideration: 2. Weed ratings on herbicide labels Use high gpa and small droplets

52 Some DRT conclusions Complex interactions: Droplet size / droplet number = pattern vs. herb. conc. 1. Nozzle type flat fan / pre-orifice / air induct. 2. Nozzle output 5 / 10 / 15 / 20 gpa 3. Speed 4 / 6 / 8 / 10 / 20 mph 4. Pressure 30 / 40 / 50 / 60 psi 5. Herbicide formulation

53 1. Nozzle type flat fan / pre-orifice / air induct. 2. Nozzle output 5 / 10 / 15 / 20 gpa 3. Speed 4 / 6 / 8 / 10 / 20 mph 4. Pressure 30 / 40 / 50 / 60 psi 5. Herbicide formulation Spray pattern at 10 gpa

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56 The Pile Effect Spray Deposit Characteristics That Influence Herbicide Efficacy

57 Spray droplets The Pile Effect

58 Herbicide deposit Spray droplets Herbicide deposit Which produces more phytotoxicity?

59 What sprayer adjustment gives a thicker herbicide deposit = > concentration? Spray droplets Herbicide deposit Which produces more phytotoxicity?

60 % control Formulation: Glyphosate Efficacy Averaged over species and 3 locations, NDSU Roundup Custom Roundup Ultra Glyphomax Plus LSD (0.05) = 9 Glyfos X-tra Touchdown Roundup UltraDry 2.5 gpa 10 gpa What would 20 gpa look like?