Irrigation sensors improve efficiency

Dozens of sensors and a crop-consulting firm keeps thousands of acres of corn properly irrigated each summer in north-central Indiana. Brian Kunce, Pro-Tech Partners, based at Leiters Ford, helps make sure irrigators understand sensor data.

Technology helped Kunce and his clients take a giant step forward. Most irrigators operate a two-sensor system, with one sensor measuring soil moisture at 12 inches, and the second at 24 inches. Kunce started with two systems. Now, there are about 80 in his area.

Key Points

• A double-sensor system helps track when irrigation should begin.

• Reading and interpreting the data is a key part of the process.

• The system pays for itself much faster in corn than in soybeans.

“The whole idea is to get a true reading of moisture content,” Kunce says. “We’re learning how to turn irrigation rigs on based on sensors, not by when the neighbor turns his rig on.”

The data collected in the field can be transmitted by cellular technology, but it’s expensive. Or it can be manually read in the field. Typically, farmers purchase sensors, and Pro-Tech Partners charges a flat fee for its assistance.

“We’re trying to pay attention to detail, and this is a service that helps do that,” Kunce explains. Pro-Tech Partners also provides grid sampling, scouting and prep work for variable rate applications.

How it works

Much of the land around Kunce is on the drouthy side. That’s why there are a large number of irrigators. The key to making sensors work, he says, is good soil-to-sensor contact. Air pockets around the sensor can interfere with measurements.

“What we do is pick the driest soil in the field,” he explains. “When it needs irrigation, the rest of the field will soon.

“This helps us stay ahead of the game,” he adds. “Once you get behind on irrigating, it’s hard to catch up. Typically, farmers save money because they don’t irrigate as often as they would otherwise. At the same time, we’ve been pleased with the yields our guys have produced.”

Smart strategies

Part of the art is knowing when to pull the trigger and irrigate, Kunce says. One strategy he recommends is determining the mount of water applied at one time by soil types. “An inch of water applied at once on light ground may be too much,” Kunce says. “We typically recommend applying less water there, but more often. On heavier soils, we may recommend applying more water each time, but less often.”

So far, the system works much better for corn than soybeans, Kunce says. Soybeans tend to be more drought resistant, while corn maturity is affected more by planting date. The payoff is on corn, not so much on soybeans.

Spectrum Technologies, Plainfield, Ill., provides sensors that clients install. Spectrum offers a wide range of sensing products, including various moisture sensors, at varying prices. Visit


Data manager: Brian Kunce helps collect data from sensors and helps farmers understand how to use it.

This article published in the June, 2010 edition of INDIANA PRAIRIE FARMER.

All rights reserved. Copyright Farm Progress Cos. 2010.