Cover Crop Interseeder: Potential for Injury from Corn Herbicides

Recent trials show that several shorter-lived residual corn herbicides can be used successfully with interseeded cover crops.
Cover Crop Interseeder: Potential for Injury from Corn Herbicides - Articles


This list includes herbicides we have evaluated for use with interseeding annual ryegrass and medium red clover in corn. The herbicides rated green have a low potential for injury, yellow, medium or moderate potential for injury, and pink have a high potential to injury cover crops. These ratings pertain to work performed in the mid-Atlantic region and is not necessarily applicable to other regions of the country. This is an ongoing project.

The table below provides some guidelines for herbicide use in the mid-Atlantic region with interseeded cover crops.

Potential for Cover Crop Injury (% Fall Biomass Reduction)

<15% = LOW (L) 15-30% = MODERATE (M) >30% = HIGH (H)

Herbicide TreatmentsProduct RateLabel RateApp TimingAnnual RyegrassRed CloverGrass-Legume Mix
SUs (2)
Resolve 25 DF0.5 oz½XPRELLL
Resolve 25 DF1 oz1XPRELLL
Triazines (5)
Atrazine (4L)1 pt½XPRELMM
Atrazine (4L)2 pt1XPREMMM
Atrazine (4L)3 pt1 ½XPREHHH
Metribuzin 75 WG4 oz1XPREHLM
Chloroacetamides (15)
Dual II Mag 7.64 EC1.67 pt1XPREHMH
Zidua 85 WG2.5 oz1XPREHMH
Harness 7 EC1 pt½XPREMLM
Harness 7 EC2 pt1XPREMLM
Outlook 6 EC½ pt½XPRELLL
Outlook 6 EC1 pt1XPREMLM
Dinitroanilines (3)
Prowl H2O 3.8 CS1.5½XPRELLL
Prowl H2O 3.8 CS3 pt1XPREHMH
PPOs (14)
Sharpen 2.85 SC1.5 fl oz½XPRELLL
Sharpen 2.85 SC3 fl oz1XPREMMM
HPPDs (27)
Balance Flex 2 SC5.3 fl oz1XPREMMM
Callisto 4 SC5.4 fl oz1XPRELHH
Impact 2.8 SC0.75 fl oz1XPOSTMHH
Keystone LA NXT2 pt½XPRELLL
Prowl + Atrazine1.5 pt+1 pt½XPREMMM
Harness + Resolve1 pt+0.5 oz½XPRELLL
Verdict 5.57 EC8 oz½XPRELLL
Lumax EZ 3.67 SE1.35 qt½XPREHHH
Acuron 3.44SC1.25 qt½XPREHHH

Potential for interseeded cover crop injury from residual corn herbicides (Pennsylvania Guidelines).