Herbicide Injury Pictures (Prostko)

If you are looking for a few good resources to help diagnose potential herbicide injury problems, check out the following web-sites:

University of California - Davis (brand new as of January 2015)
http://herbicidesymptoms.ipm.ucanr.edu

Purdue University:
http://www.btny.purdue.edu/extension/weeds/herbinj2/injuryherb1.html

Kansas State University
http://www.ksre.k-state.edu/bookstore/pubs/c715.pdf

University of Missouri
http://weedscience.missouri.edu/herbinjsymptoms/

Some New Herbicide Formulations for 2015 (Prostko)

Here is the slate of new herbicide formulations that you might read or hear about somewhere.  I have indicated if I have any data on these products (Culpepper may have some as well) and whether or not they are included in my portions of the 2015 UGA Pest Control Handbook.  Generally, UGA weed scientists will not put any new products in the “official” recs until several site-years of data are collected. 

Company	Trade Name	Active Ingredients	Major Crops	Prostko Data	Recommended by UGA in 2015 (i.e. me)
ADAMA (formerly MANA)	Latir	Flumioxazin + imazethapyr	soybean	no	no
	Pummel	Metolachlor + imazethapyr	soybean	no	no
	Torment	Fomesafen +  imazethapyr	soybean	no	no
Bayer CropScience	Diflexx	Dicamba + cyprosulfamide	corn	yes	no
	Balance Bean	Isoxaflutole	soybean	no	no
Cheminova	Bestow	Rimsulfuron	corn	no	no
	Harrow	Rimsulfuron + thifensulfuron	corn	no	no
	Statement	Fomesafen + metolachlor	soybean	yes	yes
DowAgrosciences	Enlist Duo	Glyphosate + 2,4-D choline	corn/soybean	yes	no
Dupont	Afforia	Flumioxazin + thifensulfuron + tribenuron	soybean	no	no
	Revulin Q	Nicosulfuron + mesotrione+ isoxadifen	corn	no	no
FMC	Solstice	Mesotrione + fluthiacet	corn	no	no
Monsanto	Triple Flex II	Acetochlor + flumetsulam + clopyralid + furilazole	corn	no	no
	Rowel	Flumioxazin	cotton, corn, peanut, soybean	no	no
	Rowel FX	Flumioxazin + chlorimuron	soybean	no	no
NuFarm	Spitfire	Dicamba + 2,4-D ester	corn, soybean	yes	no
	Cheetah	Glufosinate	corn, soybean, cotton	no	no
	Cheetah Max	Glufosinate + fomesafen	cotton, soybean	no	no
Syngenta	Acuron	S-metolachlor + mesotrione + atrazine + bicyclopyrone	corn	yes	no
UPI	Broadloom	Bentazon	corn, peanut, soybean, sorghum,	no	no
	Satellite	Pendimethalin	corn, cotton, peanut, soybean	no	no
Valent	Fierce XLT	Flumioxazin + pyroxasulfone + chlorimuron	soybean	no	no

Avoid Early-Harvest-Aid Applications in Soybeans (Prostko)

Soybean growers with ants in their pants, who want to use paraquat as a harvest aid, should be warned not to apply too early.  Early applications (>40% seed moisture) will likely result in significant soybean yield loss as a result of reduced seed weights (Figure 1).  The 40% seed moisture content roughly coincides with the R6.5 to R7 stages of growth.  R6.5 = Full Seed = all normal pods on 4 uppermost nodes have pod cavities filled.  R7 = Beginning Maturity = one normal pod on main stem of all plants has reached mature color (Figure 2). Official UGA soybean harvest aid recommendations can be found on page 517 of the 2014 UGA Pest Management Handbook.

Figure 2.  Soybean Reproductive Growth Stages

Fierce Section 24(c) Label For Wheat in GA (Culpepper) - For County Agents Only!

Fierce, active ingredient pyroxasulfone and flumioxazin, just obtained approval for postemergence applications in Georgia wheat as a Section 24(c) Special Local Need Label. 

Valent and I have developed this use to help growers struggling with ryegrass that is resistant to postemergence herbicides.  Our intentions for the 2014/2015 crop are to have a controlled use of Fierce allowing Valent and UGA Cooperative Extension the chance to determine if the herbicide can be used to effectively manage problem weeds while having acceptable crop injury. 

Application of Fierce:

1.  Follow the label exactly; it is listed below.

2.  Wheat must be planted 0.75 to 1 inch deep and cannot be broadcast spread.

3.  Apply Fierce at 1.5 oz/A in ONLY water when wheat is between the spike and 2-leaf stage; ryegrass needs to be spike or smaller.

4.  Apply Fierce only in water.  Notice I just mentioned twice that you cannot have anything in the tank other than clean water and the herbicide; no exceptions so don’t even call and ask!

5.  Must use 10-15 GPA; prefer 15 GPA if weeds are emerged.

6.  Do not apply with airplane.

7.  Only for wheat!!  No need to ask about other grain crops at this time, only wheat.

On-Farm Evaluations:

Several agents have been contacted directly and asked to work with Valent conducting split field comparisons treating half the field with Fierce and half the field with the grower’s standard program to improve our knowledge.  If I have not contacted you but you have a burning desire to take a look, contact your local Valent salesman which should be one of the following: 

John Altom: 352-316-1366; David Yoder 850-377-8137; or Jerry Dowdy: 803-422-6605

Crop Injury:

1. Greatest potential for injury occurs when 1) label recommendations are not followed and 2) when open/cracked seed furrow allows herbicides to directly contact the seed, when seed are planted to shallow, or when seed are planted in a deep furrow that allows herbicide concentration after a rain/irrigation event while wheat is growing. 

2.  Even when following the label, injury will occur in some environments.  This is why we are taking such a conservative approach.  With that said, our research suggests the benefits in weed control far outweigh injury concerns when following the label; you guys need to tell us if the research is accurate or not.

3.  Strongly suggest growers only try a field or two; do not treat the farm!!!!

Limited Product:

1.  We believe there will be enough product to treat about 6000 acres which is limiting but exactly what we need for this season.  

Dual Magnum Label for Georgia Broccoli, Cabbage, Cauliflower, Collards, Onion, Bell Pepper, Beans, Cantaloupe, Watermelon, Carrot, Sweet Potato, and Tomato (Culpepper)

Over the past several years, I have worked with Syngenta to increase Dual Magnum herbicide options for vegetable growers as well as to improve our previously used labels; new labels are now available. A limited amount of this information will be available through the 2015 UGA Pest Control Handbook but a label must be in hand at time of application and the label will provide much more prescriptive information. 

Important Points:

1.  Growers must have a label in hand for these uses.  These labels are written by myself and Syngenta so if there is any confusion let me know.

2.  Agents MUST NOT give growers any indemnified label; agents should obtain their own label for knowledge.  The process of Growers obtaining labels is actually the method being used to indemnify the use of Dual Magnum in these crops.  If an agent was to provide a grower the label, it may make the agent or even UGA liable if issues were to occur. 

3.  Growers should evaluate these programs on limited acres until gaining experience.  Keep in mind these labels are developed from 10 to 15 studies conducted primarily by my research in Georgia; most other pesticide labels are developed from over 200 replicated trials conducted by dozens of scientists across the country.  

4.  Support Syngenta and use Dual Magnum; no generic company has shown any desire to support such challenging label development!!!!!!!!!!!!

Obtaining the label:

1.  Go to www.farmassist.com

2.  Select products along top bar.

3.  Select indemnified labels (4^th one down).

4.  Login (first time users create login and password).

5.  For state, select Georgia and for product, select Dual Magnum in this scenario (play around and see our other labels) and then submit.

6.  Select the Dual Magnum label and crop of interest and submit.

8.  Accept waiver; this is the process making the label an indemnified label.

9.  Print label and have present during application.

Deep Turning Reduces Annual Ryegrass Populations (Culpepper and Webster)

Georgia wheat production is in jeopardy due to herbicide resistant ryegrass.  Ryegrass resistant to all currently labeled postemergence controlling herbicides has been documented and is becoming very common.  Heavy ryegrass infestations, if uncontrolled by poor management or herbicide resistance, can eliminate production. 

Ryegrass has proven that it is capable of rapidly developing resistance to any and all herbicides used for management; even more so than Palmer amaranth.  A systems approach to management is the only sustainable option and may include rotating herbicide chemistries, rotating crops, and maybe even implementing deep tillage in the more severely infested fields.

Current research is being conducted to determine the potential benefits for deep turning to reduce annual ryegrass emergence.  In our first experiment, we planted ryegrass at 0.5 inch deep and followed with no tillage (our control) or deep tillage. 

Our objectives were to determine the following:

1) Could deep turning effectively invert seed on the soil surface?

2) Could inverted seed placed 10-12 inches deep in the soil profile germinate?

Results showed a reduction in ryegrass emergence by over 99% with deep turning (figure/picture below).  Although this experiment does not address ryegrass seed spread throughout the soil profile as is the case in grower fields, it does suggest ryegrass emergence is greatly reduced when it is placed deep in the soil profile.  The next step is to better understand how long the seed will live when buried in our soils under our environmental conditions.  

Rarely will any cultural or mechanical practice effectively control ryegrass by itself.  Thus, an herbicide program will usually be needed.  See the wheat production guide or pest control handbook for herbicidal options.

Zidua Use in Wheat (Culpepper)

Zidua (pyroxasulfone), can be applied as a delayed preemergence or early postemergence application in wheat that is planted between 0.5 and 1.25 inch deep.  Zidua CANNOT BE APPLIED AS A TRUE PREEMERGENCE!

Delayed preemergence applications can occur when 80% of the germinated wheat seeds have a shoot at least ½ inch long up until spiking; applications of 0.7 to 1.0 oz/A (coarse soils) are appropriate for most Georgia fields while the rate can be increased to 1.25 oz/A on medium to fine soils.  Do not irrigate fields treated with a delayed preemergence application until wheat spiking and DO NOT apply delayed preemergence applications to broadcast-seeded wheat.

Early postemergence Zidua applications can be applied to wheat at spiking up to the fourth-tiller growth stage at a rate of 1.0 to 2.0 oz/A. 

Sequential applications may also be applied as long as the total use rate does not exceed 2.5 oz/A.

Ryegrass Control: If Zidua is activated prior to ryegrass emergence, excellent control is expected; however, if ryegrass is up at time of Zidua application then control of the emerged plants will likely be poor.  The label allows for mixtures with Axial which should control small emerged ryegrass plants that are not resistant to Axial.  Suppression of some broadleaf weeds will occur but control will not be good enough to replace broadleaf herbicide applications, especially for wild radish.

Crop Injury: Greatest potential for injury occurs when open/cracked seed furrow allows herbicides to directly contact the seed, when seed are planted to shallow, or when seed are planted in a deep furrow that allows herbicide concentration after a rain/irrigation event during wheat germination.