Volunteer potato control in corn 2007
Editor’s note: This article is from the archives of the MSU Crop Advisory Team
Alerts. Check the label of any pesticide referenced to ensure your use is
included.
Volunteer
potatoes may be a problem this year in corn fields where potatoes were
grown in 2006. Not only is it important to control volunteer potatoes to
preserve corn yield, but controlling volunteer potatoes is critical for
the management of potato pests, such as late blight disease that can be
a problem if potato is next year’s rotational crop.
Currently, there are no herbicides
available that will completely control volunteer potato. However, there
are a few different options that will provide good suppression of
volunteer potato and significantly reduce the number of daughter tubers
per plant. Michigan State University researchers (Renner, Lee, Long, and
Powell) have evaluated the effectiveness of several different
postemergence options for control of volunteer potatoes in corn.
Herbicide treatments were applied when volunteer potatoes were between 4
and 6 inches tall. From this research Callisto (3 fl oz) + crop oil
concentrate (1.0% v/v) + ammonium sulfate (17 lb/100 gal); Callisto (3
fl oz) + atrazine (0.5 lb ai) + crop oil concentrate (1.0% v/v) +
ammonium sulfate (8.5 lb/100 gal); Distinct (6 oz) + non-ionic
surfactant (0.125% v/v) + ammonium sulfate (17 lb/100gal); and Distinct
(6 oz) + atrazine (0.5 lb ai) + non-ionic surfactant (0.125% v/v) +
ammonium sulfate (17 lb/100 gal) were the best options available for
controlling volunteer potatoes, 28 days after treatment (Figure 1).
Additionally, these treatments stopped daughter tuber production,
reducing the risk of transmitting disease to the next year’s potato
crop.
Starane (1.33 pt) + atrazine (0.5 lb ai) was another treatment that also
provided good suppression of volunteer potatoes in the MSU trial (Figure 1).
However, in this trial Starane was applied at 1.33 pt/A, and is
currently labeled at 0.67 pt/A for suppression of volunteer potatoes in
corn with a maximum application rate of 1.33 pt/A per growing season.
Starane is a herbicide that has been used in small grains for a number
of years and has just recently been registered for use in field corn.
Starane has a similar mode of action as Distinct, Clarity, Stinger and
2,4-D. Therefore, it is important to remember to be cautious when using
this herbicide around sensitive broadleaf crops, such as, soybeans,
sugar beets, grapes, and dry beans, etc. Starane is labeled for preplant
and postemergence applications up to V5 (5 fully exposed leaf collars)
corn at 0.67 pt/A for suppression of volunteer potatoes.
Something to consider
Of the treatments that provided good suppression of volunteer potatoes, Callisto and Callisto + atrazine are the only treatments that can be applied to seed corn. Corn inbreds vary in their sensitivity to herbicides including Callisto, so it is important to consult the seed company on their inbred tolerances to Callisto.