Maryland Weed Reporter
http://www.agnr.umd.edu/users/weed/weedrep.htm
Summer 1996; Volume 12, No. 1
| This issue of the Maryland
Weed Reporter is to bring you
up to date on new products,
label changes and other items
crossing my desk recently. Ronald L. Ritter Extension weed control specialist RR24@umail.umd.edu  To Contact Me by Phone | ||
Field Problems |
Fall Issue of the Maryland Weed ReporterWeed Science Home PageBroadstrike Plus (Broadstrike +
Stinger) is labeled for preemergence and postemergence use in corn. As
a postemergence application, it is labeled up to 24 inch tall corn. In
no-till situations, it does a nice job suppressing emerged Canada
thistle plants.
Dual II and Bicep II are now labeled for postemergence use in corn. In general, apply before grass and broadleaf weeds
exceed the 2-leaf stage. Apply to corn not exceeding 5 - 12 inches in height.
Exceed use to have a 300 day plant-back restriction for small grains. It now has a 90 day restriction.
Frontier has changed its formulation from a 7.5 EC to a 6.0 EC. Apparently they had some freezing problems with the old
formulation. They're still using the 7.5 EC formulation in Guardsman (Frontier + atrazine).
Harness Xtra has changed its formulation also. Last year it was a 6.0 FL (4.3 lb/gal Harness + 1.7 lb/gal atrazine). This year
we're using a 5.6 FL (3.0 lb/gal Harness + 2.6 lb/gal atrazine).
Roundup Ultra will be the only Roundup product available for use in row crops. This newer formulation has its own
surfactant, is rainfast in 1 hour and only carries a "Caution" statement.
Scorpion III was originally called Broadstrike Post. We had a name change over the Winter. It's a combination of
Broadstrike + Stinger + 2,4-D. It's only labeled up to 8" corn, but it does a nice job in controlling Canadian thistle at low
cost.
Shotgun is being promoted as a new postemergence herbicide for corn. It's a combination of 2,4-D + atrazine, manufactured
by Ag-Chem.
SR Corn will be available on a limited basis this season. SR corn stands for sethoxydim-resistant corn. Sethoxydim is the
common name for Poast or Poast Plus. Thus, Poast or Poast Plus will be labeled for overtop applications on SR corn.
TopNotch is being promoted quite a bit in the no-till areas. It's a microencapsulated formulation of Surpass. Expect to see a
TopNotch + atrazine package-mix next year.
Tough has a formulation change as well. Last year it was a 3.75 EC, now it's a 5.0 EC.
Command 3ME is a new microencapsulated formulation of Command available this year. It is somewhat less volatile. I
would expect the old 4 EC formulation to stop being produced.
Flexstar is a new formulation of Reflex that will be available this year. Expect similar burn to that obtained with Blazer.
Frontier as mentioned above is now available as a 6 EC formulation and not a 7.5 EC formulation.
Fusilade, Fusilade 2000 and Fusilade DX will probably bite the bullet after this use season. Rumor has it that Zeneca will
only be supporting the continued registration of Fusion.
Fusion was recently issued labels in the Mid-Atlantic region for control of rhizome johnsongrass at the 10 fluid ounce per
acre rate. Under heavy pressure, our data has shown that this rate is too low!
Roundup-Ready Soybeans are meeting some opposition by growers locally. In order to purchase these seeds, growers are
required to pay a $5.00 technology fee per bag (50 lb. bags) and sign a grower agreement form. The form basically states
that you won't save seed and allows a Monsanto rep. on your farm over the next 3 years to make sure that you're following
the agreement. Otherwise, they can fine you and take you to court.
Roundup Ultra as mentioned above is the new Roundup formulation.
Stellar from Valent will be available for post use in soybeans. It's a package-mix of Cobra and Resource.
STS or Synchrony Tolerant Soybeans continue to show growth in our area. Synchrony (Classic + Pinnacle) does a good job
on some of our more troublesome weeds like burcucumber, giant ragweed and pokeweed.
Action by CIBA will be the name of a new postemergence herbicide for use in corn and soybeans. It's similar to Resource
by Valent in that it provides excellent postemergence control of velvetleaf.
Axiom by Bayer is a combination of a new preemergence grass herbicide with Sencor. We're looking at its use in corn and
soybeans. This is the second year we're looking at it.
Balance by Rhone-Poulenc belongs to a new class of herbicide chemistry. We're examining it for preemergence use in corn.
It's a bleacher (somewhat like Command). It inhibits enzymes that are essential for the protection of chlorophyll in plant
leaves. It has both grass and broadleaf activity. We will have it in our trials this year.
Dual Magnum is the proposed name of anew Dual formulation that may be available next year. Dual (metolachlor) is a 1:1
mixture of two pairs of isomers. One of the isomer pairs is responsible for most of the herbicidal activity in Dual. This
isomer pair will become the new Dual Magnum. Use rate is about 2/3 the use rate of regular Dual. We will have it out this
year state-wide.
Frontier may see a name change as well. Sandoz has also isolated the more active isomer in Frontier. We will be testing it
this year to examine it's herbicidal activity.
Liberty-Link Corn may be available by next year. Liberty is a postemergence herbicide that has both grass and broadleaf
activity. We used to test it under the name Ignite. It's also available in the lawn and garden market under the trade name
Finale. Liberty-Link corn will be utilized in a similar fashion to Round-Ready soybeans.
Action, as mentioned above, will be available for use in both corn and soybeans. It does a nice job in controlling velvetleaf
postemergence.
Axiom by Bayer was discussed above.
Authority by FMC may be available by next year. It's a preemergence material that has good activity on many morningglory
species, nutsedge and a number of other weeds. It's weak on ragweeds and grasses. It will probably be package-mixed with
one or two other products.
Dual Magnum by CIBA was discussed above.
Expert by CIBA is a new sulfonylurea herbicide being developed for postemergence use in soybeans. In our trials, it's done
a nice job on hard to control weeds like burcucumber and giant ragweed.
FirstRate by DowElanco is a new sulfonamide herbicide being developed for preemergence and postemergence use in
soybeans. It's chemistry is similar to Broadstrike. In our trials, it's done a nice job on many broadleaf weeds. Very weak on
post control of lambsquarters.
Frontier by Sandoz was discussed above.
Liberty-Link Soybeans will be available in the next few years. As discussed above, Liberty-Link Corn and Soybeans will
be similar to the Roundup-Ready program.
Raptor by American Cyanamid is a new imidazolinone herbicide being developed for soybeans. It's similar to Pursuit - both
grass and broadleaf activity postemergence. It seems to have a shorter residual.
The biggest problem we're faced with is the lack of performance from our preemegence herbicides in corn. With all of the
rain, many have leached out of the surface zone, leaving us with many emerged grasses and broadleaf weeds. There are
many products and voodoo mixes available. I will only mention a few at this time:
Bladex is labeled from crop emergence through the 4-leaf stage. It does a nice job on small annual grasses and broadleaf
weeds.
Basis is a new product. It's a package-mix of Matrix and Pinnacle. It is only labeled through the 4-leaf stage of corn. It also
does a nice job on small emerged annual grasses and broadleaf weeds.
Accent is labeled through the 11-leaf stage of corn. It is primarily a grass control product. I would suggest the addition of
Banvel or Clarity where broadleaf weeds exist, especially lambsquarters. For total postemergence weed control in corn,
Accent + Marksman does a super job.
Beacon or Exceed are not strong grass products. They do have activity on small giant foxtail, seedling johnsongrass and
shattercane. Corn has to be at least 4" tall before application. I always recommend the use of 4 oz./acre of Banvel or Clarity
be added to either Beacon or Exceed.
I have been receiving numerous calls about controlling Canada thistle. Right now many plants are pushing the bud stage.
This is an excellent time to apply Roundup Ultra. I would recommend a minimum of 1.5 qt./acre. The addition of 1/2
pint/acre of 2,4-D would help.
In corn, I still feel that Stinger does the best job. Use a minimum of 1/2 pint/acre, preferably 2/3 pint/acre. Scorpion III or
Broadstrike Plus are cheaper and do a good job. In our trials last year, Scorpion III did as good a job as Stinger at a much
lower cost. Marksman also does a good job although timing is critical. Up to 5-leaf corn use the full rate - 3.5 pints/acre.
From 5-leaf corn until the crop is 12" tall use 2.0 pints/acre. Lastly, Beacon or Exceed will slow the plants down. Once
again, add 4 oz./acre of Banvel or Clarity to either product.
June 25 - Painter, VA - 8:00 - 5:00
June 26 - Georgetown, DE - 8:00 - 12:00
- Vegetable Research Farm, Salisbury, MD - 1:00-3:30
- Poplar Hill Res. Farm, Quantico, MD - 4:00 - 5:30
June 27 - Wye Research Center, Queenstown, MD - 9:00 - 12:00
- Beltsville Facility, Beltsville, MD - 2:00 - 5:00
Agronomy Update Training
November 13 + 14 - Annapolis, MD
CCA School
November 19, 20 + 21 - Dover, DE
To Reach Me by Phone:
Office voice mail = 301-405-1329
Truck phone = 301-412-9858
Home = 301-490-4959
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