What Now? Flooding and Fertility

April 4, 2019

What now? Managing Flooded Soils from Central Valley Ag on Vimeo.

For many of you, these last few weeks have been surreal. The devastation and loss that I have seen farm and non-farm families hit within my own county is almost unimaginable. And while those losses are the most devastating, they certainly aren’t the only ones that we feel. As agriculture, we all know that the heart of every farm and ranch is the families and the people that are there. They are there to enrich, manage, and nourish our land. And after the human and humanitarian aspect of this flooding is taken care of, we need to shift our focus back to the land.

Over the next few weeks leading up to planting, there are some aspects and angles that I want to challenge you all to think about when it comes to management. Not only after the flood but after the specific challenges of the winter of 2018/2019. And today, I want to head right into the heart of a popular question that I'm being asked, “what has happened to the fertilizer that I applied since last fall?”

Truthfully, this question has elicited a lot of conversation between myself and a couple of close friends that I have in the world of agriculture. And after two weeks to ruminate on it, my honest answer is that I have no idea for certain, but I do have some ideas supported by facts and observations that pertain to certain situations. Before I go any further, I want to get something out there very clearly; what we do year in and year out for fertility is part of a system, and you don’t throw the baby out with the bathwater because the system breaks down once every twenty times. Our practices of pre-spring application of P-K and other products do not necessarily need to go away because of this event. But at the same time, we have to study the failure (whether perceived or actual) and learn our lessons from it as well.

As far as things I feel good about saying right now is that no-till did its job. As I look across the Northern half of Nebraska, I am amazed at how much ground does not show erosion. And even the ground that is adjacent to small creeks and streams that were raging rivers for a day or two last week showed a ton of resilience. Is the residue gone? Sure it is, but the root balls and crowns are still there holding soil and showing that the erosion was pretty minimal there. And I am going to deduce that if the soil erosion is minimal, the nutrient loss there is minimal as well. The reason why is that if the granular is gone, it should be attached to the soil. And if most of the soil is there, so are most of the nutrients.

For those soils that sit underwater, there are more questions, but history tells us that patience is the better part of virtue. We may see short term swings in fertility, but the long-term trend will hold true.

And so for today, my message may not be definitive, but it is clear. We may need fertilizer yearly for yield, but we soil sample and manage our soil fertility for insurance. The reason we build our Phosphate test into the 20 ppm range is so we can have some leeway when the weather throws us a curveball that is good or bad. You don’t have that same leeway when your soil test is 5 ppm Bray1, and we have the application for the year behind us. So for those of you that have good soil tests, the last thing I would do is blindly throw on a little more fertilizer. For those of you that don’t have a soil testing program, or don’t have your soil test built up, the last thing I would do is go blindly apply some more fertilizer at this point.

Whatever your situation is, I think the best idea instead is to invest in a plan to monitor these affected acres this season. That might mean having a couple of fields with a weekly crop scout and tissue testing plan in place. Or it could mean investing a few dollars per acre into a remote imagery platform that gives several images per year. This imagery is more than just satellite and NDVI, but very easy to understand where and when to monitor and take action. And finally, I would enroll some acres into a Nitrogen Modelling Tool such as Adapt N to have some additional feelers and reassurance out there as our spring progresses.

At the end of the day, the worst thing we can do is overreact, and the next worst is do nothing at all. We have many more resources today than even just a couple of years ago to help assure us and guide our decision-making process. If these sorts of situations apply to more than just a few acres on your farm, reach out to your trusted advisor and ask for help navigating through and building a plan that helps your confidence and maintains your budget for this cropping year.

By Keith Byerly
 

LISTEN TO THE LATEST SOIL TALK PODCAST EPISODE | SPECIAL FLOOD EPISODE



In this special episode, we discuss some of the after-effects of the flooding that covered quite a bit of CVA's territory. We have fields that have been underwater for several days or weeks. We have fields that had a high velocity of water run across them for a short duration. We have erosion. We have deposits of silt and residue. Growers will face many challenges in the coming growing season as a result.
Posted: 4/4/2019 4:35:43 PM by Kelli Reznicek | with 0 comments