http://interseedingcovers.com/herbicide-options/
Residual Corn Herbicides for Interseeding
The following herbicide recommendations are based on university trials and should provide a good direction for success. However, there are numerous factors involved in how long a herbicide may affect the cover crops planted about 5-6 weeks after corn planting. A burndown followed by a preplant residual herbicide application should be applied prior to planting corn and Glyphosate or Liberty applied just before inter-seeding if RR or Liberty Link corn is planted. A pre and post application of only Glyphosate should not be considered due to potential glyphosate resistance.
Interseeding Herbicide Examples:
- Annual ryegrass/crimson clover interseeding –
- 13 oz of Dual (1/2 rate) and .5 lb of atrazine applied early spring
- 12 oz of 2,4-D applied just before corn emergence and
- 1 qt Roundup just prior to inter-seeding.
- Annual ryegrass interseeding –
- 1 lb Atrazine and 12 oz Outlook 6 EC applied preplant
- 1 qt Roundup applied just before inter-seeding.
- Annual ryegrass interseeding –
- 16 oz Roundup burndown
- 8 oz Verdict 5.57 EC before (or at) corn planting
- Basagran before inter-seeding.
Low Risk Options for Cover Crop Injury**
**Results may vary depending on soil clay content, organic matter levels, rainfall, pH, temperature and microbial activity.
DISCLAIMER – This is the best information available. However, the user assumes all risk associated with using these herbicides at these rates and at the timing suggested.
Information based on trials conducted by Bill Curran, Penn State University
https://extension.psu.edu/evaluation-of-residual-herbicides-for-interseeding-in-corn
Broadleaf Herbicides with Potential High Risk:
- Callisto used in combination with other products
- Acuron
- Camix
- Halex GT
- Instigate
- Lumax/Lexar
- RealmQ
- Revulin
- Resicore
- Zemax
- contain >1.5 lb Atrazine at standard rate:
- Expert
- Bicep/Cinch Magnum
- Harness Xtra
Grass Herbicides with Potential High Risk that:
- contain Dualor Acuron
High Risk Options
Residual Herbicides NOT Recommended due to High Risk of Cover Crop Injury
Post Applied Herbicides
Post applied herbicides that can be applied prior to interseeding grasses, legumes or brassica combinations:
- Glyphosates
- Harmony
- Liberty
- Cadet
- Aim
- Buctril
- Basagran
Post applied products that can be applied prior to interseeding grasses:
- Basagran
- Buctril
- Aim
- Clarity/Banvel/Status
- Hornet
- Cadet
- Liberty
- Glyphosates
- Permit
- Yukom
- Callisto
- Resolve Q
- Harmony
Post applied products that can be applied prior to interseeding legumes or brassica:
- Basagran
- Buctril
- Aim
- Cadet
- Liberty
- Glyphosates
- Harmony
- 2,4-D – 1-2 pt – don’t spray 2,4-D post if inter-seeding brassicas or legumes
Copyright – 20 Post Applied Herbicides Source: Bill Curran, Penn State University
Post Applied Broadleaf Herbicides that can be applied AFTER annual ryegrass has emerged:
- Basagran
- Buctril
- Aim
- Callisto