Planting Interval of Corn after Previous Year's Soybean Herbicides

Field of soybeans
Figure 1. If a fomesafen-based herbicide (Flexstar/ Flexstar GT/ Marvel/Rumble) was applied in soybean in 2016, maintain 10 months of planting interval to corn this year.

Planting Interval of Corn after Previous Year's Soybean Herbicides April 21, 2017

Corn-soybean is the most common cropping system in eastern Nebraska. While corn growers are getting ready for planting this season, it is important to pay attention to the planting interval of herbicides applied the previous year in soybean.

Certain soybean herbicides have relatively longer planting intervals for corn, especially if they are applied post-emergence in soybean. This is particularly important because soybean planting was late last year in much of Nebraska due to May rains. This caused post-emergence herbicides to be applied later in the season than they might normally be, making it important that you pay attention to the planting interval.

For example, herbicides with fomesafen (Flexstar/Rumble/Marvel/Flexstar GT) have 10 months of planting interval for corn.  When herbicide tank-mixture is applied, consider the longest planting interval mentioned for any tank-mix partner.

Popcorn and sweet corn are more sensitive to herbicides as compared to field corn; therefore, certain herbicides have a longer planting interval for popcorn/sweet corn. For example, Pursuit has a planting interval of 8.5 months for field and seed corn, but 18 months for popcorn and sweet corn.

Resource

For more information on herbicides and planting intervals, check the latest Guide for Weed, Disease, and Insect Management in Nebraska, available to order from the Nebraska Extension Publications website.
Table 1. Planting interval (in months) of corn after soybean herbicides applied.
Soybean HerbicidePlanting
Interval
Field Corn
Planting
Interval
Seed Corn
Planting
Interval
Popcorn
Planting
Interval
Sweet Corn
Enlite 9 9 9 9 to 18c
Envive 10 10 10 18
FirstRate 9 9 9d 18
Flexstar/Rhythm/Rumble 10 10 10 10
Flexstar GT 10 10 10 10
Marvel 10 10 10 10
Pursuit 8.5 8.5 18 18
Raptor 8.5 8.5 8.5 8.5
Reflex 10 10 10 4
Rowel 1 1a 4 to 18b 3 to 18b
Rowel FX/Valor XLT 10 10 10 18
Sonic 10 10 10 18
Torment 10 10 40 18
Trivence 10 10 10 18
Valor 1 12 12 4
Warrant Ultra 10 10 12 12

a With application of Rowel at 3 oz/ac rate and at least one inch of rainfall/irrigation. Check the label if Rowel is applied at a rate of more than 3 oz/ac.
b Planting interval changes depending on rate of Rowel applied and tillage practice, check the label.
c Planting interval changes depending on processing sweet corn variety or other sweet corn variety. Check the label of this herbicide.
d Verify with seed company (supplier) the safety of herbicide on inbred lines or hybrids.