Cooperative
Extension
Service


University of Illinois
at
Urbana-Champaign


No. 8/May 16, 1997

Additional Information for Postemergence Corn Herbicides

The two previous editions of this Bulletin provided information pertaining to options for postemergence control of grass and broadleaved weed species. Table 3 provides additional information on recommended additives, rain-free periods, re-entry intervals, preharvest intervals, limits for broadcast applications, and scenarios when directed applications are necessary. Users are urged to consult the respective herbicide label for additional information.
Marshal McGlamery, and Aaron Hager,Aaron Hager, Department of Crop Sciences, (217)333-4424

Table 3. Postemergence herbicides for corn.

HerbicideAdjuvant s &;nitrog enRain free period (hr) Reentry interval (hr)PHI, daysApply broadcast up to Use drop nozzles
2,4-D amineNone684878"8" to tassel
2,4-D esterNone121278"8" to tassel
AccentCOC or NIS a + NH 4 4123020"/
V-6
20" 36"/
V-10
AtrazineCOC12122112"
BanvelNIS b or NH 4 b 424x24" c

36"
Reduces drift
BasagranCOC + NH 4 68 d 4812No limit?
BasisNIS or COC + NH 4 412306"/V-2
Basis GoldCOC + NH 4 4123012"/
V-6
BeaconCOC or NIS a + NH 4 412604"20"Splits 20" to tassel
BuctrilCOC e or NIS e 11230Pretasse l
Buctril + atrCOC e or NIS e 1123012"
ClarityUAN + COC b,f or NIS b 412x8"; 5" w/oil
Contour g COC or NIS + NH 4 1124512"
Cyanazin e h 90DFVOC b or NIS b 1212- -4-leaf
ExceedCOC or NIS + NH 4 412604"20"20"48"
Extrazin e IIh 90DFVOC b or NIS b 1212214-leaf
HornetNIS or COC, + NH 4 b 6488524"
Laddok S-12COC + NH 4 68 d 482112"
LibertyAMS4127024"/
V-7
Lightning g NIS or COC b + NH 4 1124512"?
MarksmanCOC b or NIS b + NH 4 b 448x5-leaf or 8"
PermitCOC or NIS + UAN41230Layby (36")
Poast Plus j Dash HC or COC 11260Pretasse lLayby sprays
Pursuit g COC or NIS + NH 4 11245PHI
Resolve g NIS + NH 4 1124512"
ResourceCOC + NH 4 1122810-leaf
SencorNIS or NH 4 1260Pretasse lSee tank mix partner.
Scorpion IIINIS + NH 4 b 648858"8"24"
ShotgunNone612218"8"12" or > 2 pt
StingerNone68124024"
ToughNone121268PHI
Spot treatment only
Roundup Ultra k AMS optional12456Pre tassel
Touchdown k NIS, AMS optional24490 PHI
COC = crop-oil concentrate (POC or VOC),
POC = petroleum-oil concentrate,
VOC = vegetable-oil concentrate;
NIS = nonionic surfactant;
NH4 = ammonium fertilizer adjuvant (UAN or AMS),
UAN = urea ammonium nitrate (28-0-0),
AMS = ammonium sulfate (spray grade 21-0-0),
PHI = preharvest interval.

aUse NIS only when Accent or Beacon is mixed with anything except atrazine.
bAllowed if arid or drouthy conditions exist at application.
cUp to 24 inches if nearby soybeans are over 10 inches or are blooming.
dCurrent label: "Rainfall soon after application may decrease the effectiveness."
eAdjuvants allowed if injury is acceptable.
fUse of oils (penetrants) may cause injury "if corn is > 5 inches tall."
gUse only with IMI-designated corn hybrids.
hCy-Pro and Cy-Pro AT are products similar to Bladex and Extrazine II, respectively.
iUse only with Liberty Link or GR (glufosinate resistant) corn hybrids.
jUse only with SR-designated corn hybrids.
kUse only as a spot treatment and not as an overall application in corn.