Field Notes from Kip Cullers

Question: Do you use starter fertilizer? What type and how much starter fertilizer do you use per acre? Do you prefer in furrow pop up or beside the row? Keep up the good work and thank you!

Kip: We generally do not use starter or popup fertilizer for a couple of reasons. First of all, our planters are not set up for starter and more importantly, we don't think we need starter. We apply the bulk of our nutrients in the fall with soil applications of poultry litter plus some humate and work it all into the top 8 to 10 inches of soil. Then during the season we mostly supplement nutrient supply with foliar applications of micronutrients (Mn, Zn, B, Mo and Cu) plus ammonium sulfate applied in the pivot irrigation water.

Question: What are the typical yield differences between your commercial fields and contest fields?

Kip: Like all yield contest farmers, we know where the highest-yielding portions of our fields are year in and year out. Therefore in a normal year, our pivot-irrigated commercial corn will yield anywhere from 50 to 100 bu/acre less than our highest corn contest plot yields (which are always on irrigated ground). Our commercial dryland fields will yield considerably less. In a good year they will be about one half the yield of our best contest plot. For example, this year, we have already harvested some 175 bu/acre corn in dryland fields which is above average. But when we harvest the contest plots, they hopefully will be about double that.

Question: I notice several farmers burning corn fields after harvest. Is it not better to work this matter into the soil. I've heard that a lot of the soil benefit from corn is in the root matter so burning doesn't hurt that much. What is your opinion? One of the reasons they burn some of these fields is to get prepared to plant wheat.

Kip: Like everything else, there are trade offs with burning off fields. It's a quick, easy (and cheap) way to clear a field and prepare it for immediate planting back into a crop like wheat. My opinion is that the soil benefits from the return of both root tissue and above-ground crop residues. We rarely use field burning in our high-yield fields. We do everything we can to maintain or increase the amount of organic matter in our soils.

Question: What is the most important foliar fertilizer fungicide that you feel should apply after pod fill has started? Also, you talk about ammonium sulfate as foliar, what does it do to benefit the plant? Also, at what rates to apply? How often?

Kip: We apply a mix of foliar nutrients including N, S, Mn, B, Zn, Cu and Mo. We feel they are all important in making sure no nutrient is limiting plant growth. Since N is used in the largest amounts by the plant, you could say it's the most important. We put on about 5-10 lbs of N from ammonium sulfate per application. Fungicides are also an effective tool in limiting plant stress. We do rotate active ingredients if we make more than one fungicide application to the same crop. This keeps the plant pathogens from becoming resistant to a single fungicide.

Question: Do you apply any micro nutrients in addition to NPK ?

Kip: We apply a mix of foliar nutrients including N, S, Mn, B, Zn, Cu and Mo. We feel they are all important in making sure no nutrient is limiting plant growth. Since N is used in the largest amount by the plant, you could say it's the most important.

Question: What variety are the soybeans, and how tall are you ?

Kip: We grow a number of soybean varieties in our yield contest plots from Group 3's to late Group 4's. Right now we are the most excited with 94M80, the same variety we won with last year. It is growing rapidly and flowering profusely. They are already taller than me at 5 ft. 10 inches.

Question: I'm intrigued by the benefits of this Hummate product that I read that you have used. Have you been able to document an increase in soil organic matter with it's use? How did you apply it?

Kip: We apply several hundred pounds of Hummate product each fall as a soil broadcast application. This amount contains a small amount of carbon compared to what is already in the soil's organic matter so we have not been able to measure a change in soil OM yet. The reason we use it is because of its other nutrient release characteristics.

Question: Can you talk about gray leaf spot? It has seemed to set in earlier then other years. Remind me what or if anything can be done at this point. Last year I had it but seemed to still have very good yields. Did I lose yield and really not know it.

Kip: Gray leaf spot is not a problem for us in our corn fields because we use one or more fungicide sprays to control all corn leaf diseases. Fungicide applications after the blister stage to control GLS may be too late to be cost effective.

Question: Is it true that you spray pesticides on your crops that are off label such as spraying Regent insecticide foliar? I have also heard you use vinegar as a foliar feed in soybeans. If this is true, what benefit does this provide?

Kip: We carefully follow all pesticide label instructions. We do use foliar applications of small amounts of vinegar, especially on our soybean crops. Not everyone agrees that this practice does anything, but I feel that it does help keep the soybean crop from growing too "rank". We do feel that the slight acidity of vinegar mildly "shocks" the plant to keep it blooming and setting pods without growing so tall. With our high levels of fertility and frequent irrigation, our main concern with our soybeans is excessive plant height and lodging.