University of Illinois

No. 16/July 10, 1998

Herbicides for Sorghum

Wet holes in corn fields continue to persist across much of Illinois. Many fields have been replanted to corn, some to soybeans; and standing water remains in others. Some producers may consider replanting some of these areas to sorghum instead of soybeans when field conditions permit. The herbicide previously applied may influence this replant decision.

What soil-applied or postemergence corn herbicides allow sorghum as a recrop option? Table 1 contains information about recropping restrictions for corn herbicides. If the field was previously treated with products containing acetochlor, flumetsulam, imazethapyr, simazine, nicosulfuron, rimsulfuron, or primisulfuron, sorghum would not be a recrop option. Other corn herbicides allow recropping to sorghum but may have a 1- or 2-month rotational interval. Additionally, some herbicides that allow recropping to sorghum also require that the seed be treated with Screen or Concep safener.

Table 1. Corn herbicide recropping restrictions, months
Herbicidea Comments Corn Sorghum Wheat Oats
Acetochlorand itspremixes
DoublePlay w/EPTC NY NY 4 2Y
FulTime w/atrazine NY NY 15 2Y
Harness acetochlor NY NY 4 2Y
HarnessXtra 5.6L w/atrazine NY NY 15 2Y
Surpass,TopNotch acetochlor NY NY 4 2Y
Surpass 100 w/atrazine NY NY 15 2Y
Atrazineand itspremixes;simazine
AAtrex/Atrazine pH < 7.2 AT AT NY 2Y
Bicep II w/metolachlor AT ATc NY 2Y
Bicep LiteMagnum w/metolachlor AT ATc NY 2Y
Buctril +atrazine w/bromoxynil AT AT NY 2Y
Bullet w/alachlor AT ATc NY 2Y
Extrazine w/cyanazine AT 1 15 15
Guardsman w/dimethenamid AT ATc NY 2Y
Laddok S-12 w/bentazon AT AT 15 15
Marksman w/dicamba AT AT 10 10
Princep simazine AT NY NY 2Y
Flumetsulamand itspremixes;clopyralid
Broadstrike+ Dual w/metolachlor AT 12 4.5 4.5
Hornet w/clopyralid AT 12 4 4
Python flumetsulam AT 12 4 4
ScorpionIII w/clopyralid +2,4-D AT 12 4 4
Stinger clopyralid AT 10.5 AT AT
Imazethapyrand itspremixes
Contour w/atrazine 8.5f 18 9.5 18
Lightning w/imazapyr 8.5f 18 4 18
Pursuit imazethapyr 8.5f 18 4 18
PursuitPlus w/pendimethalin 8.5 18 4 18
Resolve w/dicamba 8.5f 18 4 18
Sulfonylureas andtheirpremixes
Accent nicosulfuron (A) AT 10d 4 8
Accent Gold A +R + Hornet AT 12 4 8
Basis thifensulfuron +rimsulfuron (R) AT 10 4 8
Basis Gold A + R + atrazine AT 10 10 18
CelebrityB&G dicamba +nicosulfuron AT 10d 4 8
Beacon primsulfuron (C) 0.5 8 3 8
Exceed C + D 1 10 3 3
Spirit C+ D 1 10 3 3
Peak prosulfuron (D) 1 1 AT AT
Permit halosulfuron 1 2 2 2

Table 1, continued. Corn herbicide recropping restrictions, months
Herbicidea Comments Rye Alfalfa Clover Soybeans
Acetochlor and itspremixes
DoublePlay w/EPTC 2Y 2Y 2Y NY
FulTime w/atrazine 2Y 2Y 2Y NYb
Harness acetochlor 2Y 2Y 2Y NY
Harness Xtra 5.6L w/atrazine 2Y 2Y 2Y NY
Surpass, TopNotch acetochlor 2Y 2Y 2Y NY
Surpass 100 w/atrazine 2Y 2Y 2Y NYb
Atrazine and itspremixes; simazine
AAtrex/Atrazine pH < 7.2 NY 2Y 2Y NYb
Bicep II w/metolachlor NY 2Y 2Y Nyb
Bicep Lite Magnum w/metolachlor NY 2Y 2Y NYb
Buctril + atrazine w/bromoxynil NY 2Y 2Y NY
Bullet w/alachlor NY 2Y 2Y NYb
Extrazine w/cyanazine 15 18 18 NYb
Guardsman w/dimethenamid NY 2Y 2Y NYb
Laddok S-12 w/bentazon 15 18 18 NY
Marksman w/dicamba 10 2Y 2Y NYb
Princep simazine NY 2Y 2Y NY
Flumetsulam and itspremixes; clopyralid
Broadstrike + Dual w/metolachlor 4.5 4 26Fba AT
Hornet w/clopyralid 4 10.5 26Fba 10.5e
Python flumetsulam 4 4 26Fba AT
Scorpion III w/clopyralid + 2,4-D 4 10.5 26Fba 10.5e
Stinger clopyralid AT 10.5 18 10.5e
Imazethapyr and itspremixes
Contour w/atrazine 9.5 18 40Fba 9.5
Lightning w/imazapyr 4 9.5 40Fba 9.5
Pursuit imazethapyr 4 4 40Fba AT
Pursuit Plus w/pendimethalin 9.5 9.5 40Fba AT
Resolve w/dicamba 4 9.5 40Fba 9.5
Sulfonylureas andtheir premixes
Accent nicosulfuron (A) 4 10 10 0.5
Accent Gold A +R + Hornet 4 10.5 26Fba 10.5e
Basis thifensulfuron +rimsulfuron (R) 18 10 18 0.5
Basis Gold A + R + atrazine 10 18 18 10b
Celebrity B&G dicamba + nicosulfuron 4 10 10 0.5
Beacon primsulfuron (C) 3 8 18 8
Exceed C + D 3 18 18 10-18g
Spirit C+ D 3 18h 18 10-18g
Peak prosulfuron (D) AT 10 22 22
Permit halosulfuron 2 9 9 9

Fba = Field bioassay needed (see label), NY = next year, 2Y = 2nd year
aOther corn herbicides have no significant recropping restriction except Banvel, Clarity, 2,4-D, and Eradicane have replanting limits forsoybeans.
b2Y (2nd year) if applied after June 10 with high atrazine or July 1 with Basis Gold)
cConcep or Screen seed protectant needed
dl8 months if pH > 7.5
e18 months if <15 inches rainfall received and if soil has < 2% organic matter.
fIMI corn hybrids may be replanted AT (anytime).
gExceed I-70 to I-80, 18 months or use STS soybeans. Exceed or Spirit above I-80, 18 months to soybeans.
hSouth of I-70; 22 months north of I-70.

What are other postemergence herbicides that can be used in sorghum? Table 2 lists several postemergence herbicides that may also be applied to sorghum. All products containing atrazine must be applied before sorghum reaches 12 inches in height. Consult the respective herbicide labels for additional application information and restrictions. Pay particular attention to specified crop rotational intervals for many of these herbicides, as applications late in the 1998 growing season may influence planting during 1999.

Table 2. Postemergence herbicides for use in sorghum

HerbicideGrain sorghumForage sorghum
Buctril +atrazineYesYes
Laddok S-12YesYes

aDo not apply to sorghum grown for seed.
bApplications of Prowl or Treflan must be mechanically incorporated afterapplication.

Marshal McGlamery ( and Aaron Hager (, Crop Sciences, (217)333-4424