The Root of the Problem

The Root of it All from Central Valley Ag on Vimeo.

by Mike Zwingman

by Mike Zwingman

Today’s topic is root development.  Or rather, the lack thereof.

We’ve had a ridiculously odd spring that’s put soil temperatures on a real roller coaster ride.  There’s bound to be some weirdness in our plants as a result and that weirdness starts in the roots.

Root development, or again, lack thereof, should have a major impact on some of the decisions we make later in the season in regards to water and nitrogen management, so it’s important that we know what’s going on under the surface.  Making assumptions about how roots are doing is always problematic, but more so when the season has been as wonky as it’s been.  So in the coming weeks, we have some digging to do, friends, and some root architecture to inspect.

This spring saw very wet soils across CVA territories for a prolonged time.  Wet soil is slow to warm, meaning that our soils were also cooler longer than normal.  Given that soil temperature impacts the growth of roots and that cooler soil makes for less vigorous root development—there’s very little development at all when soil temperatures are in the lower 50s—we shouldn’t be totally surprised to see smaller roots than we might be expecting based on other seasons.

This is the weirdness that begins in the roots.


The weirdness that stems from this occurs when a corn plant works to rapidly develop green and white tissues on the limited energy intake possible given a smaller root system.  It can cause a mismatch between how roots look and how stands look (ie stands can look great even though roots don’t) and mislead even astute growers as to the potential of their crop.

There’s little better we can do than go get a shovel, the digital tool most useful to us right now.  (Get it?  Digital?  As in your fingers?  Ha.)  Over the coming weeks, we need simply to dig up some plants and check things out, like any impact of sidewall compaction.  We need to take note of any clipping or discoloration/browning/mushiness.  We need to note what overall development looks like.  And we need not to freak out at what we see but rather to write it down and evaluate the cause be it disease, insect damage, environmental limitations, or mechanical causes.

Because we’ll use these notes to 1) make water and nitrogen decisions throughout the season, and 2) compare with our yield maps come harvest to evaluate the impact of any limited root development and our management henceforth.

The notes you take now will help you prioritize how to spend money this season.  Knowing limitations on your acres—the yield limiting factors—will help you get the biggest bang for your buck and to avoid spending uselessly.

Because most of the problems caused by small roots can’t be cured—not with an extra shot of N or TLC with water.  And that’s okay.  But that’s a discussion for later.  Right now, we need to know what we have.  So dig and take notes, because there isn’t any decision to make at the moment.  What you see and learn now will start coming into play in two or three weeks when we sidedress and whenever it is we start the pivots.  We’ll work with whatever it is we have to optimize yield and profit.