It’s officially late spring.

Your corn is shooting up, and its roots are digging down. And that means something else…

Corn rootworm larvae have bellied up to the buffet.

The primary concern with these insects may be adult feeding during pollination, but it’s worth the effort to identify a potential problem before that critical time.

And as your reliable partner in the field, LG Seeds is here to help you successfully scout corn rootworm in your fields.

The Tools

First off, you’ll need a few simple supplies. A tile spade, a few five-gallon buckets, and access to a hose or pressure washer are all you need for a successful scouting session.

The Method

You’ve gathered your tools, and now you’re ready to start scouting for the little buggers. When scouting, just remember these five simple steps: pick, dig, soak, rinse, evaluate (PDSRE).

Or, if you were an acrostic rockstar back when you were learning the nine (or is it eight?) planets, this might be more up your alley:

Please Don’t Surrender to Rootworms—Ever (PDSRE).

Pick: Walk about 100 feet into a field and pick out three plants that are uniform in size and evenly spaced from each other.

Dig: Dig in a circle around each plant—about a six to eight-inch radius. Dig down as deep as possible, trying to keep the root mass intact. Pro tip: If you’re evaluating more than one hybrid or trait, make sure you label each plant with a water-resistant marker.

Soak: Soak the roots in a five-gallon bucket of water for 15 minutes. If rootworm pressure is severe, you’ll see them floating around in the bucket after that 15-minute soak. (Houston, we have a problem…)

Rinse: Turn on the hose and rinse off those roots. A low-pressure nozzle is best, but if you have a pressure washer, just be sure to stand back—you’re gently rinsing soil off roots, not power-cleaning the north side of your tool shed.

Evaluate: Check out each root node and look for damage from feeding corn rootworm larvae. (Reminder: a root node is a “circle” of roots. Think of the plant’s brace roots—those are all surrounding a node.) Use this root rating scale to measure the root damage:

0.00—No feeding damage is noted (this is the lowest rating possible).

1.00—One node (again, that circle of roots), or the equivalent of an entire node, is eaten back to within approximately 1.5 inches of the stalk (or back to the soil line on the 7th node).

2.00—Two complete nodes have been eaten.

3.00—Three or more nodes eaten (this is the highest rating possible).

Note: Your rating doesn’t have to be in whole numbers. Damage in between “complete nodes eaten” is noted as the percentage of the node missing. Examples:

1.50 = 1½ nodes eaten

0.25 = ¼ of one node eaten

The Problem and The Fix

Corn rootworm feeding can cause significant yield loss and increased lodging. Furthermore, the damage they cause can inhibit water and nutrient uptake and provides an entry point for secondary pathogens into the plant. Basically, it’s a big problem.

So what can you do if you find significant pressure? 

First off, work with your LG Seeds agronomist and discuss your options for addressing the issue in the current growing season.

And if more than one node is eaten off, with each root on the node 1.5 inches or less, be sure to discuss preventative management practices for next year.

From seed selection to planting and rootworm scouting to harvest, LG Seeds will be by your side—no nonsense, no excuses. 

That’s support you can take to the field.