There's a reason yield maps sold A LOT of tile

Published on: 14:57PM Jun 07, 2013

Chip Flory

From The Editor

June 7, 2013

Hello Pro Farmer Members!

I'll admit... I was shocked when I looked at the table from Iowa State University that estimates the impact of late-planting on corn yields. Corn planted today at 35,000 population through June 15 in Iowa would have just 54% of its maximum yield potential. That's roughly equal to corn planted May 5-15 at just 10,000 plants per acre. Scary stuff... and that help makes it exceptionally clear why many growers consider a Prevented Plant claim to be their best option at this time. Making the PP claim even more attractive is that many growers carry 80% or even 85% Revenue Protection, rather than the 75% RP many are using in examples.

This is also the first time for many (almost all) Iowa corn growers to consider PP... and they're impressed by the financial certainty the PP claim provides. Potential revenue from switching to soybeans might be close in revenue, but it doesn't have the financial certainty that a PP claim does. That's making it very attractive to many growers that are trying to move bean seed from the tender to the dirt, but waterlogged fields are making it impossible to do!

That was one of my learning experiences this week... here's another: Lower-quality soils in the wettest areas of the Midwest look like they'll perform better than the high-quality soils. It kind of makes sense... lower-quality soils have lower water-holding capacity and, therefore, are draining better than thick, black dirt.

And it's very clear where tile lines are this year. Soils above and close to tile lines drain more quickly than points furthest way from the tiles. Over and near tiles, corn plants are developing much more quickly than plants furthest away from tiles. But, there's plenty of people that assume the later-developing corn will catch up and yield won't be hurt "that bad."

If the corn will "catch up," then why were yield monitors and yield mapping the BEST tile-selling campaign EVER for the drainage industry!?!

When yield monitors were first put on combines and started collecting data from every inch of fields, and that data was digitally mapped for the first time, growers started noticing streaks of higher yields alternating with areas of lower yields. Most figured it out right away... others had to make a trip to the field.

The higher-yield streaks were the areas above and near tile lines... lower yielding areas were the spaces between tile line. The result? More tile! Instead of tile every 120-foot across a field, most cut it in half by dropping in another line down the middle. Some cut it even further by dropping two evenly spaced lines in the 120-foot space. If they already had a line every 60-foot, some even cut that in half.

It's hard telling how many bushels were lost in the decades before the tile explosion... which is why we can EASILY say we've lost more bushels to too much water than we have to drought over the last several decades. You've got to move the water (not moisture) away from the root zone, but even the doubled and tripled amount of tile in the country compared to 20 years ago isn't enough to move water from record high April-May rainfall totals in Iowa.

So... while the corn between the tile lines this year that is clearly behind corn over and near tile lines right now might appear to catch up, I'll bet you a dollar right now the yield maps will show the tile-line yield streaks this fall.

Here's another thing I learned this week: Corn started tasseling in the Gulf states this week. A friend in Mississippi called to let me know. The crop there was generally planted on time, and then it started to rain. Corn got off to a quick start, and actually grew too quickly to let some guys into the field to sidedress nitrogen. One of this friend's neighbors was actually flying on urea and spreading 100 lbs. per acre over chest-high corn. (I guess he doesn't have access to a Hi-Boy!)

Another one: Anhydrous applicators might end up being an important tillage tool this spring. I knew that saturated soils are devoid of oxygen and no oxygen means no root growth or nutrient up-take. Some are considering using the anhydrous knives to open up soil to air it out -- well, actually air it IN. They say the knife is the perfect tool to use because a field cultivator might clip roots that are growing horizontally rather than down.

That's it for now...

 Have a great weekend!

Follow me on Twitter at @ChipFlory

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