Field Corn Weed Control Update (Prostko)

Field corn weed control does not have to be difficult.  Just about any of the herbicide programs that growers are using in Georgia do a good job of controlling most weeds, especially Palmer amaranth, when applied to small plants (<3" tall). Want some proof? Check out the following pictures from my field corn plots that I rated earlier today (click on pictures to make them larger).  Just so you know, these herbicide treatments were applied 17 days after planting with a CO2-powered backpack sprayer calibrated to deliver 15 GPA at 3.5 MPH using AIXR 11002 nozzles.

The most troublesome weed in Georgia field corn, in my opinion, is annual morningglory.  Field corn growers who struggle with morningglory should seriously consider a post-directed/lay-by application of Evik (ametryn) sometime after their initial POST treatment was applied.  Check out page 70 of the 2017 UGA Pest Control Handbook for more information about Evik.  The minimum corn height for post-directed applications of Evik is 12".  If Evik is tank-mixed with glyphosate, post-directed applications can be applied up until 48" tall corn (RR2 hybrids).

Glyphosate/Atrazine/Adjuvants in Field Corn (Prostko)

A common question this week from field corn growers is "Do I need to add a crop oil concentrate (COC) when applying glyphosate + atrazine?"  For you Roundup babies out there, Atrazine + Prowl + COC was one of the most common and effective field corn herbicide treatments in Georgia before the introduction of RR-crops.  Thus, it is tough for seasoned field corn growers to consider not using a COC.  With that said, there is no need to use a COC when a fully "loaded" formulation of glyphosate is used.  Fully "loaded" glyphosate formulations already contain enough adjuvants.  In fact, COC's have been known to cause antagonism when mixed with glyphosate.  

Fully "loaded" glyphosate formulations include the following:  Abundit, Barbarian Max, Buccaneer Plus, Cornerstone 5 Plus, Credit/41Extra, Credit Xtreme, Duramax, Durango DMA, Gly-Fos Xtra, Glysort Plus, Gly Gold Extra, Gly Star Plus, Helosate Plus, Helosate 70, Mad Dog Plus, Makaze, Roundup PowerMax, Roundup WeatherMax, Showdown, Touchdown CT, Touchdown IQ, Touchdown Total.

In my own research program, I have not been using additional adjuvants with Roundup + Atrazine for a very long time (Figure 1).

If a grower uses a glyphosate formulation that is not loaded at all or is partially loaded, then he/she should consider adding a non-ionic surfactant (NIS) @ 0.25% v/v or 1 qt/100 gal.

Figure 1. A common field corn weed control program.  No adjuvants were used with the POST treatment of Roundup PowerMax + Atrazine.  FYI, this entire herbicide program costs approximately $16.50/A (excluding application costs).

Replanting Field Corn and Weed Control (Prostko)

The recent frosty weather has resulted in the need for some corn fields to be replanted. Some of those fields may have already been treated with a PRE application of atrazine. Since it is likely that these fields will have to be re-tilled, there have been some questions on what to do next.  Here are a few comments to consider:

1) Field corn is extremely tolerant of atrazine so crop injury should not be a concern. 

2) The maximum amount of atrazine that can be legally be applied in a field when both PRE and POST applications are used is 2.5 lbs ai/A (i.e. 2.5 qts of 4L).

3) Atrazine could be used again PRE on the replant but that would limit the amount that could be applied POST.

4) In those fields that have already been treated with atrazine and are tilled/replanted, I would suggest that growers switch to another PRE herbicide such as Dual II Magnum 7.64EC (16-21 oz/A) or Warrant 3ME (48 oz/A).  This way, growers can use an additional 1.5 qts/A of atrazine in their POST application of glyphosate or other favorite and remain within the label restrictions. 

4) When using these chloracetamide herbicides in field corn, it is also a good idea to make sure that there are no potential hybrid sensitivity issues (really not that common).  Generally, this information can be obtained from the seed companies.  

Pioneer: https://www.pioneer.com/CMRoot/Pioneer/US/products/stewardship/2016-corn-herbicide-ProdList.pdf

Dekalb: No specific ratings for amide tolerance?

Mycogen:  Field corn hybrids rated for careful management (i.e. limit overlap and high rates) include the following: MY90R27RA, MY13K77RA, CNX157144S3, F2F499, and TMF86H77RA. 

Sprayer Clean-Out and Tank-Cleaners (Prostko)

With all the ado about 2,4-D and dicamba-tolerant crops theses days, there is some concern about sprayer cleanout after application of Enlist Duo, Engenia, Fexapan, and Xtendimax.  I would encourage all applicators to read and follow the specific sprayer clean-out instructions listed on the herbicide labels. Here are some useful links: 

2017 Enlist Duo Product Use Guide (automatic download of document - sprayer clean-out procedures listed on pages 20-21)
http://www.enlist.com/~/media/enlist/enlist-ahead/resource-pdfs/2017_enlistallcrops_pug_final.ashx

Engenia Clean-Out Recomendations:
http://agproducts.basf.us/campaigns/engenia/assets/pdf/Engenia-Spray-System-Cleanout-TIB.pdf

Fexapan Sprayer Cleanout
http://www.dupont.com/products-and-services/crop-protection/soybean-protection/articles/sprayer-cleanout.html

Xtendimax Cleanout (video presentation)
https://youtu.be/LzywJ-YSta4?list=PLWKeHPsbiIP7URV05Y03YTMfYxGLmQ3sF

I called a few local chemical dealers and the following are some commercial tank-cleaners that are currently being sold in Georgia (listed in no particular order):

1) WipeOut XS
https://s3-us-west-1.amazonaws.com/www.agrian.com/pdfs/WipeOut_XS_Label.pdf

2) Valent Tank Cleaner
https://www.valent.com/Data/Labels/1714-B-ValentTankCleaner.pdf

3) Nutra-Sol Tank-Cleaner
http://www.cdms.net/ldat/ldDC2000.pdf

4) All Clear
https://s3-us-west-1.amazonaws.com/www.agrian.com/pdfs/All_Clear_Label4.pdf

5) ProTank Cleaner
http://www.winfield.com/cs/groups/lolweb/@winfield/documents/web_content/ndjf/mzax/~edisp/36142_301402.pdf

6) Neutralize
http://www.cdms.net/ldat/ldDC1000.pdf

One-on-One Trainings, Using Pesticides Wisely, Buying Seeds or Herbicides, Cotton and Vegetable Circulars – Addressing Agent Questions (Culpepper)

One-on-One Trainings: 

Question: Can the one-on-one training replace the Using Pesticide Wisely Training? Answer: no, no and NO. One-on-one trainings are to compliment the Using Pesticides Wisely Training but cannot but used to replace it. If you do not attend the Using Pesticide Wisely training then you cannot legally be the person responsible for an application of 2,4-D or dicamba in tolerant crops (soybean or cotton).

For those of you that did not join in the mock one-on-one trainings, it was recorded. Scott Utley and Wade Parker have both sent the link out numerous times. Your efforts with the one-on-one trainings have the potential to be monumental and keep in mind you will collectively accomplish something that has never been done………….ever !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Using Pesticides Wisely: 

Question: What happens if I miss all of the Using Pesticides Wisely Trainings? 
Answer: You implement a sound alternative program without 2,4-D or dicamba in-season. By March of 2017, there will have been 36 meetings over 3 years, pretty sure several meetings have been close to each applicator or person responsible for the application. Additionally, well over 2000 people have now attended the training. Not sure what else needs to be said???

HELP!! In 2015 some growers registered under farm names. This is not a big deal at all but I need your help getting actual grower names for those farms. So if someone from your county registered as a farm name, please e-mail me the grower or growers names, pesticide license number, address, and their e-mail (if they have one). Again, this would have only happened for the 2015 list. We cannot give a Using Pesticide Wisely card to the farm, so please help us address this issue.

Buying Seeds or Herbicides: 

Question: If I don’t take the Using Pesticide Wisely training does that prevent me from buying any seed or herbicides? 
Answer: No, absolutely not. Restricting the purchase of any seed or herbicide may promote the use of older formulations of 2,4-D or dicamba which we do not want any part of. It really is simple, the training allows one to LEGALLY make an application of 2,4-D or dicamba in-season for tolerant crops. Labels making this clear can be found at the Department of Agriculture’s Using Pesticides Wisely Website: www.agr.georgia.gov/24c.aspx

2017 Cotton and Vegetable Circulars are uploaded to the UGA Weed Science Web-Page @ www.gaweed.com. All three cotton circulars as numerous vegetable circulars should be able to be printed as needed. Of course, as I travel the state, you are welcome to the ones I have already laminated.  FYI, Prostko also has his weed control recommendations listed for all of his crops on our web-site.

Dicamba-Tolerant Crop Updates (Prostko)

Lots of action this week for the new dicamba formulations that can be used on dicamba-tolerant cotton and soybean.  Here is some news:

Fexapan with Vapor Grip:  Dupont's dicamba-DGA formulation for use on tolerant crops received its federal approval.  State labels are soon to follow?

A copy of the EPA approval letter can be obtained here:
https://www3.epa.gov/pesticides/chem_search/ppls/000352-00913-20170207.pdf
  
For additional technical information about Fexapan:
http://www.dupont.com/products-and-services/crop-protection/soybean-protection/products/fexapan.html

Engenia (BASF):  Additional tank-mixtures (9 adjuvants) have been approved for use including the following: Induce, Astonish, Class Act Ridion, Contrast, Fastrate, Impetro, Intact Xtra, Jackhammer Elite, Kabak Plus.

Xtendimax with Vapor Grip (Monsanto): Additional nozzles (20 total) are now approved for use.  See below:

                                                                 Operating Pressure (PSI)

Manufacturer	Nozzle Type	10	20	30	40	50	60	70	80	90	100
Greenleaf Technologies	TADF-D11003		Min 20		Max 40
	TADF-D11006		Min 20			Max 50
	TDXL-D11003		Min 20		Max 40
	TDXL-D11004		Min 20			Max 50
	TDXL-D11005		Min 20				Max 60
	TDXL-D11006		Min 20				Max 60
Hypro	ULD12004		Min 20		Max 40
	ULD12005		Min 20		Max 40
Lechler	ID11003			Min 30	Max 40
	ID11004			Min 30	Max 40
	ID11005			Min 30	Max 40
	ID8004			Min 30	Max 40
TeeJet® Technologies	AI11003			Min 30	Max 40
	AI8003			Min 30	Max 40
	AI8005			Min 30	Max 40
	TTI11003		Min 20				Max 60
	TTI11004		Min 20				Max 63
	TTI11005		Min 20				Max 60
	TTI11006		Min 20			Max 50
Wilger	DR11010		Min 20		Max 40

2017 UGA Recommended Soybean Varieties (Freeman and Prostko)

The following is the current list of UGA recommended soybean varieties for 2017.  To make it on this list, a soybean variety must 1) perform, at least, at or above the 2-year average in yield across 6 Georgia locations (12-test average); 2) must not be susceptible to stem canker; and 3) other considerations include new herbicide tolerances or nematode resistances.  

I. Coastal Plain and Piedmont (Early Planted)
MG V ¨AGSouth AGS533LL* AGSouth AGS568RR* ¨AGSouth AGS5911LL* ¨Armor 53-R16* AR UA5213C* AR UA5612* ¨Bayer HBK LL4950* Dyna-Gro 39RY57* Dyna-Gro S56RY84* NK S52-Y2 Brand* §NK S58-Z4* Osage* Pioneer P54T94R* §Pioneer P56T12SR* ¨SS 5511NR2* ¨SS 5513NR2* §SS 5615NR2* ¨SS 5711NR2* Terral-REV 55R53* Terral-REV 56R63* Terral-REV 57R21* ¨US Seeds Halo 5:01* ¨US Seeds Halo 5:45*	MG VI ¨Asgrow AG6834 §Bayer CZ 6060 RY §Bayer CZ 6109 LL §Bayer CZ 6316 LL Croplan R2C6764 Dyna-Gro S65RY73 §Dyna-Gro S67RY25 §Meherrin SH 6515 LL ¨NK S67-R6 Brand §Pioneer P67T25R2 ¨SS 6713NR2 ¨SS 6810NR2	MG VII AGSouth AGS738RR AGSouth AGS757RR ¨AGSouth AGS787RR AGSouth AGS Woodruff Asgrow AG7535 GENRR2Y            ¨Asgrow AG7934 §Bayer CZ 7007 LL ¨Bayer CZ 7070RY ¨Croplan R2C7622 §Dyna-Gro S72RS36 Dyna-Gro S77RY85 ¨Dyna-Gro S74RY15 NK S74-M3 Brand §Pioneer P76T54R2 Santee §SS 7215NS R2 §USG 77J25RS ¨USG 77S40R2 ¨USG 77S63R	MG VIII AGSouth AGS828RR Motte
II.  Coastal Plain and Piedmont (Late Planted)
		MG VII AGSouth AGS738RR AGSouth AGS757RR ¨AGSouth AGS787RR AGSouth AGS Woodruff Asgrow AG7535 GENRR2Y            ¨Asgrow AG7934 §Bayer CZ 7007 LL ¨Bayer CZ 7070RY ¨Croplan R2C7622 §Dyna-Gro S72RS36 Dyna-Gro S77RY85 ¨Dyna-Gro S74RY15 NK S74-M3 Brand §Pioneer P76T54R2 Santee §SS SS 7215NS R2 §USG 77J25RS ¨USG 77S40R2 ¨USG 77S63R	MG VIII AGSouth AGS828RR Motte

III.  Limestone Valley (Early Planted)
MG V ¨AGSouth AGS533LL* AGSouth AGS568RR* ¨AGSouth AGS5911LL* ¨Armor 53-R16* AR UA5213C* AR UA5612* ¨Bayer HBK LL4950* Dyna-Gro 39RY57* Dyna-Gro S56RY84* NK S52-Y2 Brand* §NK S58-Z4* Osage* Pioneer P54T94R* §Pioneer P56T12SR* ¨SS 5511NR2* ¨SS 5513NR2* §SS 5615NR2* ¨SS 5711NR2* Terral-REV 55R53* Terral-REV 56R63* Terral-REV 57R21* ¨US Seeds Halo 5:01* ¨US Seeds Halo 5:45*	MG VI ¨Asgrow AG6834 §Bayer CZ 6060 RY §Bayer CZ 6109 LL §Bayer CZ 6316 LL Croplan R2C6764 Dyna-Gro S65RY73 §Dyna-Gro S67RY25 §Meherrin SH 6515 LL ¨NK S67-R6 Brand §Pioneer P67T25R2 ¨SS 6713NR2 ¨SS 6810NR2	MG VII AGSouth AGS738RR AGSouth AGS757RR ¨AGSouth AGS787RR AGSouth AGS Woodruff Asgrow AG7535 GENRR2Y            ¨Asgrow AG7934 §Bayer CZ 7007 LL ¨Bayer CZ 7070RY ¨Croplan R2C7622 §Dyna-Gro S72RS36 Dyna-Gro S77RY85 ¨Dyna-Gro S74RY15 NK S74-M3 Brand §Pioneer P76T54R2 Santee §SS 7215NS R2 §USG 77J25RS ¨USG 77S40R2 ¨USG 77S63R
IV.  Limestone Valley (Late Planted)
	MG VI ¨Asgrow AG6834 §Bayer CZ 6060 RY §Bayer CZ 6109 LL §Bayer CZ 6316 LL Croplan R2C6764 Dyna-Gro S65RY73 §Dyna-Gro S67RY25 §Meherrin SH 6515 LL ¨NK S67-R6 Brand §Pioneer P67T25R2 ¨SS 6713NR2 ¨SS 6810NR2	MG VII AGSouth AGS738RR AGSouth AGS757RR ¨AGSouth AGS787RR AGSouth AGS Woodruff Asgrow AG7535 GENRR2Y            ¨Asgrow AG7934 §Bayer CZ 7007 LL ¨Bayer CZ 7070RY ¨Croplan R2C7622 §Dyna-Gro S72RS36 Dyna-Gro S77RY85 ¨Dyna-Gro S74RY15 NK S74-M3 Brand §Pioneer P76T54R2 Santee §SS 7215NS R2 §USG 77J25RS ¨USG 77S40R2 ¨USG 77S63R

Footnotes:

*    -    Recommended only for highly productive, irrigated fields.

¨   -    To be dropped from recommended list in 2018.

§   -    New for 2017.