Last spring, we planted two different fields of cover crops, had acquired a new (to us) strip-till unit for fertilizer application, and we were finally able to upgrade to auto-steer. We had planned to strip-till a few acres last fall but just couldn't get a wiring issue figured out before the ground froze. It turned out to be a very simple fix (the ground and power wire to the meter sensors were swapped).
However, I was disappointed we wouldn't be able to compare fall and spring applications with the strip till unit. Just like all equipment that someone is unfamiliar with, it took a little while to learn the ins and outs of the strip till bar and air cart this spring. However, once it was dialed in, we were within 2 pounds per acre accuracy when applying phosphorous (P) and potassium (K). I was very happy with the results.
We learned it pays to take density measurements of each load of fertilizer, as they often differ. If the density was not entered correctly into the rate controller it could cause inaccurate application rates. We applied 70 pounds of potash and 130 pounds of MEZZ per acre on our corn ground and it didn't plug once. The air cart didn't miss a beat for us and I was really impressed. That's not to say we didn't have problems though; our ground has a lot of subsurface rocks and we went through a great deal of shear bolts for the fertilizer knives.
We were initially running about 8 inches deep and shearing bolt after bolt. After moving up to 6 inches deep, the shearing frequency went down, but didn't stop completely. I was worried the fertilizer might be a little too close to the seed and affect germination, but we didn't notice any problems during the entire growing season. I was also very interested to see if their would be any difference between 6 and 8 inch depths and my observations favored the 6 inch depth. The corn greened up a few days earlier and maintained a slight height advantage into mid-July at the 6 inch depth. I'm not sure why, but I believe the corn root didn't have as far to go to hit the fertilizer band.
My biggest lesson this spring was how poor quality fertilizer can really cause problems. We did some custom strip till work for a neighbor who had a different fertilizer supplier and things didn't go well. The rate was not extremely high, only 300 total pounds per acre (I had previously applied 460 pounds per acre for my dad with no problems). This fertilizer mix was basically the same as what I had applied, except he added 100 pounds of urea per acre (my dad added 260 pounds of urea).
No problem, I thought. The batch of fertilizer had been sitting on the tender truck for the previous five days and when we started to auger it into the air cart a bunch of wet, half dissolved, muck fertilizer poured right into the cart and down to the meter at the bottom. We spent the next hour cleaning the wet mix out of the meters. Once I finally got going, knife after knife began to plug. I couldn't go 20 feet without plugging a fertilizer knife.
The batch of fertilizer was peppered with small, ping pong ball sized clumps of hard fertilizer and rocks. The rocks and clumps were small enough to pass through the screen when loading onto the air cart, but not small enough to pass through the fertilizer knives. I even found a rock the size of my smart phone on the air cart screen after we had loaded fertilizer; glad the screen caught that. The fertilizer batch was also partly saturated with moisture. All this made for a very, very long night. I wanted to finish before the rain started, so I kept battling through the bad fertilizer batch and finally finished at about 3:15am. It sure felt great to crawl into bed that night. So if you take away anything from this post; let it be my experience with a bad batch of fertilizer.
After going through this ordeal, I would recommend that fertilizer be brought directly from your trusted source, and if at all possible, do not let it sit in the tender truck or the air cart overnight. My main task before we strip-till this fall is to build a smaller screen to use while loading fertilizer into the cart. It may take longer to load but avoiding potential headaches and downtime is a much more important priority.
From Farmers Business Network: The Corn Nitrogen Guide
We’ve created this guide to help share the knowledge that FBN℠ members and agronomic experts have taken advantage of to use nitrogen more effectively while understanding and minimizing N costs for their corn crop.
You Will Learn:
- 6 Factors That Are Affecting Your N Strategy
- Yield Goals vs. Profit Goals: Determing Your N Rate
- Network Trends: Nitrogen Use Across the Corn Belt
- Nitrogen Efficiency of Top Varieties
The views expressed in this article are the author's alone and not those of Farmer's Business Network, Inc., its affiliates or members.