Yes, this is a rhetorical question just to get a thought out and on to paper, well the blog. Two weeks ago, I wrote an entry with this paragraph, ” There are many moving parts to getting ready to a new crop year. Checking on equipment, ordering seed, pesticides, fertilizer, fuel, and parts as you discover the need for replacements, selling last year’s crop, booking some of 2021 crop, and making sure your finances are in all order. I’m sure I didn’t list everything but we all get the picture. ……” I certainly hope that you are making progress as we get closer to planting season.
I’ve been thinking about some of those things that I have seen over the years where I’ve had to tell a grower that there was nothing he could do to solve the problem in his current corn crop since the only fix is at planting. In the over-whelming majority of cases, the problem was preventable and led to significant yield losses. In this case, I am referring to nematode infestations. Sting and stubby root nematodes will cause the most significant losses since they are ectoparasites and feed on/and prune the roots . Root-knots can be severe but corn can be managed in such fashion that losses are sometimes mitigated through extra fertilizer and careful irrigation. There are no measures that a grower can take to mitigate the damage from stings or stubby roots once the crop is in the ground and the plant is growing.
If you didn’t take the time to sample for potential nematode problems on your farm so as to identify those fields with nematode infestations, and have had problems in the past two or three years, then I encourage you to take preventive actions this planting season. Yield losses from these nematodes have easily exceeded 20 to 30 bushels per acre. In 2019, Dr. Bob Kemerait, in UGA trials demonstrated a 50+ bushel yield loss in one study comparing a nematicide treated plot to the control. Given the price of corn as of this entry (March board: $5.34; Sept. $4.68), that impact shows a revenue loss of $234 to $267 per acre. Small infestations early can cause big losses in the end. Please don’t take nematodes lightly. If you are leasing a new farm or just purchased a new farm, I encourage the use of a nematicide as a preventative insurance against nematodes.
Thankfully, more products are emerging that can help prevent these type of yield losses. Let’s review what is available. Telone II while difficult to find, is an excellent soil fumigant that is highly effective but must be applied carefully and, obviously before planting. Apply the chemical as a row treatment at 3 gallons per acre. Use suitable ground application equipment that will insure placement of the fumigant at least 12-14 inches below the final planting surface. Seal the soil immediately after application. Soil sealing may be accomplished using bedding or strip till equipment that allows or moves the soil over the furrow after applying. After application and sealing, leave the soil undisturbed for at least a week to 10 days before planting.
Another solid choice is Counter 20 G at 5.25 lbs/ac. It is a granular product which would have to be applied via a dry box. This should be applied in the furrow to provide best control/suppression of nematodes. Remember, ALS-inhibiting herbicides must not be used in corn that has been treated with Counter 20G. If your weed control program requires an ALS-inhibiting herbicide then do not choose this option for controlling nematodes.
There is a new liquid in-furrow treatment from Bayer that has shown effectiveness in UGA trials in suppressing nematodes. Propulse (fluopyram + prothioconazole) is an option if the other two are not good options for your farm and is applied at a 4.0-8.0 fl oz/ac. In Propulse, you are getting a fungicide with the fluopyram. If you use Propulse, I suggest the higher rate than the lower rate as the higher rates appear more effective on the ectoparasites. This new chemistry can mix well with an in-furrow insecticide but NOT liquid fertilizers. If you normally apply a liquid fertilizer in the row then you will have to have separate tanks & tubes to apply the fertilizer and Propulse at planting.
(ADDENDUM: The following was added 1/29 . ” I find my internet skills sometime wanting and am careful when recommending chemistries for use. I could not find the Vellum (fluopyram) label at a time when I was writing the above statement. Dr. Kemerait had spoken clearly to me about the recommendation of Vellum and it being a good choice as well. A 3 oz per acre rate is currently in review for a 2 EE label and is expected by planting time. The difference is Vellum lacks the fungicide found in Propluse. It was late when writing this and since I couldn’t seem to find the label, I chose to leave it off. He graciously provided me the label so I could add the product to this entry. Thanks, Dr. Bob.)
One other thought. If nematodes have plagued my fields for years or I was going to plant a field where I had no knowledge of the history, I would not hesitate to apply a fungicide and a insecticide in-furrow WITH the nematicide to give my corn seedling the best chance at getting ahead of any stress. This area would be a prime a candidate for Telone II however it has limitations in separate equipment and availability but is most effective. If that is not an option, I would certainly consider protecting my yield potential with nematicides, insecticides and fungicides at planting time since a problem that early can certainly undermine any yield goal you may set. I know what you are thinking…yes today corn seed comes treated with fungicides and insecticide treatments. But, I have seen where additional help is needed to protect the early season growth particularly in cold, wet conditions. Think about it.