From the Field 7-22-2020

Corn is beginning to tassel across the state and planes are beginning to fly on fungicide applications. Now is the optimal timing for R3 fungicide applications on soybeans as well as VT applications on corn. Tar spot in corn has been frequent topic since it first hit hard in 2018. The graphic below shows confirmed tar spot incidence by county the last five years. We can see that tar spot has consistently spread to most southern Wisconsin counties each year. Scouting fields has shown us that infection may start in the upper leaves because of how easily the spores travel by wind. At this stage in the corn plant, top leaves are the most crucial to the photosynthesis process leading to grain fill. These top leaves can be protected by an aerial fungicide application. When selecting a fungicide from the many options available, it’s important to choose one with a broad spectrum control, multiple modes of action, and solid residual.

Talk with your local Landmark agronomist if you have questions about whether fungicide will be a good fit.

The crops in the far eastern part of the state are really starting to take off and are looking good. We had a stretch of weather in mid-June through early July when we were short on moisture; since then, the east has caught some rain that really pushed the crops along.

A large portion of our corn is at VT or almost there. Fungicides have been a hot topic with growers; there is a high potential for yield on this year’s corn crop and the weather has been conducive to disease issues. Commodity prices are still suppressed, but protecting or improving yield potential is an easy way to overcome lower prices. Lower crop prices have driven some growers to purchase more cost-effective types of seed, but lower-traited corn appears to have increased the incidence of disease.

While walking some corn fields for disease, I found fields that had a lower trait package of corn. While walking, I also found severe silk clipping, goose-necking, and extreme ear tissue feeding on this corn. These three things introduce plant health issues as well as fall standability and harvesting issues. The images below illustrate the aforementioned health issues as well as the culprit: western corn rootworm and northern corn rootworm beetles. These fields will need to be sprayed by air with both an insecticide and fungicide to preserve what crop is left. I know that prices are low and a lower-traited corn may be cheaper, but talk to your agronomist before making a decisions based on price, as it’s not always the best agronomic choice.

Our Stine dealership has been a great thing this year when it comes to soybean weed control. The Stine E3 beans have given our agronomists multiple tools for controlling weeds, especially waterhemp, this year. Having the ability to use Enlist, Liberty, and RoundUp on these beans has allowed many of our fields to be extremely clean while not having the application constraints that the Xtend beans have. Moreover, the Stine beans look extremely good, with a very bushy bean that is dark green in color. If you didn’t use these beans this year, I recommend talking to your agronomist about how the Stine beans and E3 herbicide package can help your bottom line in the upcoming growing season.

Our third crop hay is moving right along to cutting maturity. The alfalfa caught a couple of timely rains and it looks like it may outyield our second crop. Fungicide applications on hay are becoming popular on hay in our area again. We did a few fungicide trials for growers for this crop and they can already see the increased leaf retention all the way down the plant. This increased leaf retention will increase quality as well as tonnage per acre. If you’re not using fungicide on your hay, contact your local Landmark agronomist about the benefits of it.

Lastly, wheat yields seem to be spread across the board with some in the 80s and 90s, with some in the 50s. Straw yields seem to be lower than normal, with most growers getting as low as they can when cutting to increase the yield.