Tar Spot in Northeast Iowa

Keep an eye out for this as your doing late season crop scouting, checking corn standability, yield estimates, etc.  I was out doing some spot checks yesterday in Benton, Tama, and Bremer Counties and found this in 3 out of the 5 corn fields I was in.

Our national land grant universities have a helpful map here showing the current geographic distribution of this disease.  Iowa State University has written several articles about this, as have the University of Illinois and the University of Wisconsin among others.

Based on what we’ve seen in the past few days, my guess is that the occurrence of Tar Spot will be far more prevalent than we realize – lots of folks will stop scouting fields once we get into the mid/late grain fill period, and disease identification becomes more and more difficult as crops start to senesce. 

This will be an important discussion to have with your seed dealer over the late fall and winter. Check university trials (like Wisconsin) that publish disease ratings with their trial results. Several fungicides are either labeled or have a FIFRA 2ee recommendation for Tar Spot control (as mentioned here).


Time to start thinking about fall soil sampling

Although it’s still summer, harvest of seed corn and early maturing soybeans is just a few short weeks away.  With continued uncertainty in commodities markets likely to extend into the foreseeable future, getting a fall game plan in place now that will maximize nutrient use efficiency and eliminate unnecessary expenses is more important than ever.  Getting quality soil sampling on 2.5 to 5.0-acre grids provides you with a level of detail sufficient to make variable rate applications of phosphorus, potassium, and lime.  Many will say lime alone pays for the sampling.  In addition, average savings per acre on dry fertilizer will run about $5-$10 per year.  With sampling costs running in the $8-10$/ac range, that’s just $2-$2.50 per year for fields sampled on a 4-year rotation. The payoff to this added level of management is significant – just a couple bucks per acre per year to make $10 or $20.

North Iowa Agronomy Partners is an independent third-party provider of soil sampling. We aren’t in the business of selling more fertilizer or other inputs - our recommendations are based only on what you need to reach your crop yield and fertility goals.  All NIAP samples are taken by a Certified Crop Advisor – none of our work is out-sourced to seasonal or part time help.  We pull 12-14 cores at each grid or sample zone to ensure accuracy, whereas most of our competitors only pull 6-10. Once the samples are back from the lab, we will provide you and your retailer a prescription to VRT P, K, and lime on your fields. You will also receive an easy to understand printed booklet with all your results and recommendations.

Our software allows us to work with any retailer and any type of machine or rate controller. All of the data we collect is yours – at any time, we will provide you with shape files, results, and other related information to allow you to transfer your results to any software platform.  Because we work with both retailers and farmers, our direct prices are often $1-$3 per acre cheaper than your local coop or service provider.  We bring value to our clients by being an unbiased independent company, providing accurate and repeatable results, and by offering recommendations tailored to each farmer and field.

Please contact us HERE to set up your fall sampling now!


-          Jeremy Sills, CCA

Hot & Dry Weather Impacting Crops

Hot and dry conditions have been impacting most of eastern Iowa over the last month.  Scattered storms brought some relief late yesterday, but the crops are still thirsty in many parts of the state. Earlier crops planted in April and early May have deeper roots than those planted in late May and into June. The more mature corn is still being stressed by excessive heat and lack of moisture, but the shorter younger corn leaves are rolling and are very stressed as their root development is much shallower. So how did we go from one of the wettest springs on record to one of the hottest and driest growing seasons?

The term being used to describe the conditions we are experiencing lately is a “Flash Drought.” The difference between a normal drought and a flash drought are the length of time to reach drought stage. Typical droughts take several months to a year to develop whereas flash droughts occur within a one to two-month time frame. We have received below average precipitation coupled with above average temperatures that have rapidly depleted soil moisture levels taking us from one extreme to the other within two months.

As I write this a large storm is moving across Iowa bringing some much-needed rain, but temperatures are forecast to remain hot and humid through the weekend. As we know pollination is adversely affected by hot temperatures - extreme heat over the next few days may adversely impact some of the earlier planted fields.

One of the best ways to reduce weather stress on our crops is to improve our soil health. Reduced tillage allows for better soil structure, improved water infiltration, and increased soil organic matter. Cover crops used in tandem with reduced or no-till systems can help speed up the process of improving soil health and structure.  With higher organic matter levels and improved soil structure comes the ability to be more resilient to extreme weather events, whether that’s excessive rainfall in the spring or hot and dry weather in the summer.

If you are interested in learning more about how you can increase your farms ability to be more resilient during these challenging times just click here and we will be happy to schedule a free consultation to discuss different approaches to increasing yields while improving soil health and total ROI for your farm!

Written By: Jeremy Sills, CCA

Spring 2019 Planting Season

It has been a challenging spring for farmers to say the least. Following a fall with little to no anhydrous applied, spring brought significant logistical hurdles for Iowa retailers. Many producers had to wait for NH3 tanks which extended the already delayed N applications. Some producers switched to urea while others will sidedress most of their nitrogen later in the season so they could get planters going sooner. Corn planting started in Tama and Benton Counties the third week in April abruptly halting on Friday, April 26 ahead of the cold and wet snap we are currently under. Many were weighing the risks and work loads of to plant or not to plant leading up to Friday with a week of rain and cool temperatures in the forecast.

According to ISU’s Environmental Mesonet East Central Iowa has accumulated only 20 GDD’s since Friday and 80-90 GDD’s since the previous Friday, April 19. There is a lot of corn that has been sitting in wet, cool soil conditions since the 20th. Time will tell the extent to which imbibitional chilling will effect germination and stand establishment. (https://crops.extension.iastate.edu/blog/mark-licht/imbibitional-chilling-or-cold-injury Click on this link to learn more about imbibitional chilling.) The 4” soil temperatures across Iowa on April 30th were in the 40’s.

The foreseeable forecast has a chance of rain 6 out of the next 10 days with highs in the 50’s and 60’s. If you have emergence concerns give North Iowa Agronomy a call and we can help you make the best decision on what next steps to take.

The producers that opted to plant soybeans before corn may have less worries as soybeans can recover better from stand loss, but again, time will tell.  Another possible benefit of switching to bean planting is that it reduces possible anhydrous burn on corn seedlings if it hasn’t had enough time to mineralize.


-Jeremy Sills, CCA, TSP



Welcome to North Iowa Agronomy Partners new website! We are very thankful for the year we had in 2018 and could’t be more excited for the 2019 growing season. Last year we added two full time employees Bailey and Jeremy. Both are Certified Crop Advisers and NRCS Technical Service Providers. This year we will be offering professional drone services with NDVI, NDRE, and aerial imagery with a Sentera fixed-wing drone and their FieldAgent Software platform. The software can be linked with many existing data management providers such as MyJohnDeere and Encirca. Please explore our new site and let us know what you think!

We will be hosting a Field Day in Brandon, IA February 15 from 11-1:00 about Edge of Field Practices! Click here for more info or visit www.cedarriversolutions.com