ndsucpr_L_sm_W.jpg (13414 bytes)
weeds_Logo_Lg.jpg (6562 bytes)


ISSUE 5  JUNE 3, 1999

 

SLN LABEL ISSUED FOR CHICKPEAS

    Commissioner of Agriculture Roger Johnson has issued a special local needs exemption
(SLN) for Tough SEC, allowing North Dakota garbanzobean producers to use the herbicide
to kill post_emergent weeds. The label was issued because only preemergence herbicides are
currently approved for garbanzo beans. North Dakota is among the leading producers of garbanzo
beans, also known as chickpeas. Applicators must follow all instructions, warnings and precautions
on the Section 3 and SLN labels. The SLN label must be directly attached to theproduct container
and be in the user's possession during application. Tough SEC is manufactured by Novartis Crop
Protection.

    One or two applications of 24 fl oz/A may be made per crop with a minimum of 20 days between
applications. Adjuvants are prohibited from use with Tough. For best control of broadleaf weeds,
applications should be targeted to actively growing weeds by the fourth stage (3 inches in height).

 

1999 SMALL GRAIN HERBICIDE UPDATE

Achieve 40DF (Zeneca)
    Mode of action: ACCase Inhibitor
    a.i.:
tralkoxydim
   Crops: HRS and durum wheat, and barley.
   Comments: Federal Section 3 registration granted. 40WDG formulation may change in the future
                        to a different concentration. Wide crop stage application window: 2-lf to boot.
                       SuperCharge (U.S.) / Turbo-Charge (Canada) oil adjuvant is included in a separate
                       container in the box and should be used at least at 0.5% v/v. It has MSO type oil +
                       buffer (phosphate esters) to alter (lower) water pH. ADDITION OF AMS AT 7 TO
                       15 LB/100 GALLONS WATER IS REQUIRED. Wild oat are more susceptible than
                        foxtail. Also controls ryegrass and barnyardgrass. Dry weather before and after
                        application decreases grass control. Severe antagonism when tankmixed with SU's and
                        phenoxy amines. May tankmix with Buctril, Bronate, Stinger, and/or MCPA ester.
                        Synergistic activity with Bronate. Supplemental label expands tank mix options to Starane
                        and Harmony GT (not in ND).  Resistant wild oat populations have been documented
                        in Canada. Wild oat control is reduced when Achieve is applied in intense UV light,
                        during midday as opposed to evening, and at low GPA.  Reducing water carrier pH to
                        below 6 increases wild oat and grass control with ‘dim’ (Achieve, Poast, Select) herbicides
                        due to greater absorption of neutral charged molecules than in the anionic form at higher pH.
                        Greater absorption may also increase when adding ammonium fertilizer which changes
                        molecules to NH3 form. Solution should be sprayed soon after mixing because of acid
                        hydrolysis degradation in low pH conditions.


Aim 40DF (FMC)
    Mode of action: PPO Inhibitor
    a.i.:
carfentrazone
   Crops:
Wheat and durum.
   Comments:
$4/A at 0.33 oz/A. Contact, nonresidual, broadleaf herbicide. Narrow weed spectrum
                        kochia (+ALS resistant) and pigweed. Always apply with other broadleaf herbicides,
                        such as phenoxy herbicides or bromoxynil. Crop leaf burn may occur with oil adjuvants
                        and hot weather. DO NOT apply to barley.


Banvel/Clarity (BASF)
    Mode of action: Plant growth regulator
    Crops:
Corn and wheat.
   a.i.:
Banvel = dicamba - dimethylamine salt
           Clarity = dicamba - diglycolamine salt
   Comments:
Aerial applications of Clarity allowed on most all registrations. Clarity label may expand
                       window of application in corn. BASF allow Microflo the right to market Banvel in registered
                       crops.   BASF will retain Clarity for all Banvel markets. Heavier salt formulation of Clarity
                       reduces risk of drift compared to Banvel or SGF but droplet or particle drift is equal among
                       formulations and caution should be used using any dicamba brand.
                       Dicamba Herbicide

Banvel = dicamba - dimethylamine
Banvel SGF = dicamba - Na+
Clarity = dicamba - diglycolamine
Fallowmaster = dicamba - acid + Roundup
Marksman = dicamba - K+ + atrazine
Resolve = dicamba - Na+ + Pursuit
OpTill = dicamba - acid + Frontier


Discover (Novartis) - In U.S.
Horizon (Novartis) - In Canada
    Mode of action:
ACCase inhibitor
   a.i.: clodinafop
   Crops: HRS and durum wheat.
   Comments: Registered in Canada. U.S. registration expected in 2000. Controls grass weeds -
                        excellent on wild oat at reduced rates. Wild oat is more susceptible than foxtail.
                       Controls barnyardgrass.  Less antagonism with broadleaf herbicides than fenoxaprop
                       or Achieve. Do not use on barley.


Harmony GT (DuPont) 75DF
    Mode of action: ALS inhibitor
    a.i.:
thifensulfuron
    Crops:
Small grains, and possibly Imi canola
    Comments:
Only available in Pacific NW in 1999. Formulated as the original Harmony 75DF
                        instead of 25DF. Pinnacle will be phased out. GT stands for Grass Tankmix because
                        of its limited antagonism with POST grass herbicides. Tankmixes  include Achieve,
                        Assert, Avenge, Dakota, Hoelon, and Tiller. EPA has been petitioned to allow use
                        on Imi canola.

Imi wheat - Wheat resistant to Raptor is in development and varieties and use expected in 2003.
Control most annual grass and broadleaf weeeds.


Maverik (MON 37500) 75DF (Monsanto)
    Mode of action: ALS inhibitor
    a.i.:
sulfosulfuron
    Crops:
Spring and winter wheat
    Comments:
Registration expected in 2000.  A very long residual, SU herbicide applied PRE or
                        POST at 0.67 oz/A for cheatgrass/downy brome, quackgrass and broadleaf weed
                        control in winter wheat. Better efficacy with early postemergence applications.
                        Has foxtail and wild oat activity. Poor control of jointed goatgrass.  MSO adjuvants
                        provide greater herbicide enhancement.


MKH 6562 (Bayer) - 70DF
    Mode of action: ALS Inhibitor
    a.i.:
flucarbozone
    Crops: Wheat, including durum and winter.
    Comments: Sulfonylaminocarbonyltriazolinone chemstry found by looking for fungicides.
                        In development in HRS wheat and durum - NOT BARLEY - for control of
                        grass and broadleaf weeds at 0.27 lb ai/A (20-30 g ai/ha) to wheat at 1 to 6-leaves.
                        Must use NIS and combine with another broadleaf herbicide.  Controls green foxtail,
                        wild oat, mustard species, redroot pigweed, and annual smartweed. Suppresses yellow
                        foxtail. Other experimental compounds with different modes of action are in development.

Paramount (BAS 589) (BASF) - In USA
Accord 75DF (BASF) - In Canada
    Mode of action:
Plant growth regulator
    a.i.:
quinclorac
    Crops:
Wheat, fallow, sorghum, and noncropland
    Comments:
Registration for fall and preplant applications granted in April 1999. Registration
                         for in-crop use expected in 2000 or 2001. Rates at 0.17 to 0.33 lb/A. Labeled on
                        foxtail, barnyardgrass, cleavers, volunteer flax, and sowthistle in Canada. Most crops
                        may be planted one year after application except flax, chick pea, field pea, and sugarbeet
                        which must wait 24 months after application before planting. Accord antagonizes Assert.
                        Use only MSO adjuvant. Used in Canada to control DNA/ACCase resistant green foxtail.
                        Some research show greater consistency of field bindweed control at rates 0.37 to
                        0.5 lb ai/A. Adequate control of field bindweed will require multiple applications if use
                        less than 0.37 lb ai/A.

Puma (AgrEvo)
    Mode of action
: ACCase inhibitor
    a.i.: clodinafop
    Crops: HRS and durum wheat, and barley.
    Comments: New labeled tank mix options include:
    Puma at 0.33 pt/A for green foxtail and foxtail millets =
    Buctril or Bronate at 1 pt/A or MCPA ester at 0.75 pt/A, or Curtail M at 1.75 pt/A, or Stinger at
    0.25 to 0.33 pt/A, or Express at 1/6 oz/A, or Harmony GT at oz/A, or Harmony Extra at 3/10 oz/A,
    or Amber at 0.28 oz/A, or Peak at 0.5 oz/A, or Ally at 1/10 oz/A or Banvel/Clarity (wheat only) at 2 fl
    oz/A, or Banvel SGF (wheat only) at 4 fl oz/A, or Starane at 0.66 pt/A, or Tordon at 1 to 1.5 fl oz/A.

    Puma at 0.4 pt/A for yellow foxtail plus proso millets =
    MCPA ester at 0.75 pt/A, or Curtail M at 1.75 pt/A, or Stinger at 0.25 to 0.33 pt/A, or Peak at
    0.5 oz/A, or Banvel/ Clarity at 2 fl oz/A, or Banvel SGF at 4 fl oz/A, or Starane at 0.66 pt/A, or
    Tordon at 1 to 1.5 fl oz/A.

    Puma at 0.67 pt/A for wild oat and barnyardgrass =
    Buctril or Bronate at 1 pt/A or MCPA ester at 0.75 pt/A, or Curtail M at 1.75 pt/A, or Stinger at
    0.25 to 0.33 pt/A, or Harmony GT at oz/A, or Harmony Extra at 3/10 oz/A, or Peak at 0.5 oz/A,
    or Ally at 1/10 oz/A, or Starane at 0.66 pt/A, or Tordon at 1 to 1.5 fl oz/A.

    Rave (Novartis) 58.8% DF
    Mode of action: ALS inhibitor + Plant growth regulator
    a.i.:
5:1 ratio of triasulfuron (Amber) + dicamba (Banvel/Clarity)
    Crops: Wheat, pasture, rangeland, and CRP
    Comments: 2 to 4 oz/A. Registered in ND but not actively promoted in wheat in ND due to
                         the very, very, very long carryover of Amber and rotation restriction rotation to
                        sensitive crops broadleaf crops.

Starane (UAP) - IN U.S. - PGR
Attain (Dow) - IN CAN
(180 g/L fluroxypyr and 564 g/L 2,4-D ester)
    Mode of action: Plant growth inhibitor
    a.i.:
fluroxypyr
    Crops: Wheat, barley, oat and chem fallow.  Corn and sorghum expected in future.
    Comments: No residual. Excellent control of kochia, including ALS and dicamba resistant. Provides
                        control or partial  control of wild buckwheat and nightshades. Premixes available with
                        2,4-D ester =Starane Plus Salvo and with MCPA ester=Starane Plus Sword. ND 2(ee)
                        labels allow reduced rates of Starane at 0.5 pt/A ~ $5.70/A Starane + Salvo and Starane
                        + Sword at 1 pt/A.

Some evidence that some kochia populations may exhibit varying degrees of natural tolerance to Starane.

Richard Zollinger
NDSU Extension Weed Specialist
rzolling@ndsuext.nodak.edu

BEWARE OF COOL, WET WEATHER AND SOME HERBICIDES ON CORN

    Cool, wet weather can jeopardize the effectiveness of herbicides used in corn and can sometimes
contribute to crop injury. Wet weather can lessen the effectiveness of the herbicides used by washing
chemicals from the weeds or by leaching the chemicals through porous soil profiles away from weed
roots. Even worse, the weather can slow crop metabolism of the applied herbicides. With cool, wet
weather, some pre-emerge and early post herbicides are slowed when being metabolizing through
crop plants. Slow crop plant growth usually translates to even slower metabolism of herbicides
through crop plants.

    Ohio State has already reported corn leafing-out underground rather than emerging properly in
areas which are experiencing cool, wet weather. Two herbicides used in these areas are Lasso and
Dual. If soil is not crusted severely, the corn often still emerges and continues to grow without yield
loss. However if the soil surface is crusted, corn can have a difficult time breaking through the soil
surface barrier with already emerged leaves. In areas where soil moisture has remained, the corn
should be able to come through the surface and will also be helped by a quicker degradation of the
alacholor or metolachlor with the excess soil moisture and warming temperatures. Watch crops
carefully, excess moisture also stresses the young corn seedlings which in turn accentuates the slow
metabolism problems and can allow the corn to become more susceptible to cool, wet season
diseases lurking in the soil and on remaining crop residue.

    Another metabolism problem that has been seen this year is with Balance on corn. Corn generally
has a good tolerance to Balance because corn can rapidly metabolize the active ingredient, isoxaflutole,
to nonphytotoxic forms within the crop plant. However some farmers in Illinois have reported a
"bleaching" symptomology along the margins and tips of new corn leaves in areas experiencing cool
weather and very wet soils. This weather has been slowing overall crop growth and thus slowing the
plant's ability to rapidly metabolize the herbicide. When the amount of the active herbicide within the
plant exceeds the plant's ability to metabolize the chemical, crop injury symptoms have resulted. Most
injury has been more distinctive along headland rows where there probably was a double-up of the
application. Also, soils lower in organic matter and also those with a higher sand content may have
more herbicide in solution and thus more available for plant uptake. Recent field scouting has suggested
that injury from use of Balance which has been present for a week or longer has been showing signs
of recovery with warming weather.

    During cool, wet seasons, it is imperative that crop scouting be done regularly--weekly, if possible.
Crop plants slowed in growth due to weather conditions are more susceptible to stresses from
herbicides, insects, diseases as well as weed competition. Carefully evaluate crop concerns seen
in the field in order to accurately diagnose the problems.

Denise A. McWilliams
Extension Crop Production Specialist
dmcwilli@ndsuext.nodak.edu

 


cprhome.jpg (3929 bytes)topofpage.jpg (3455 bytes)tableofcontents.jpg (4563 bytes)previous.jpg (2814 bytes)next.jpg (1962 bytes)