FORT McCOY, Wis. — Thursday’s training started around a sandbox for some of the soldiers of the 833rd Engineer Company.

Soldiers use sand tables to map out where their objectives are. The tables are exactly what they sound like they are. They stand about three feet high and are four feet by six feet.

The sand is a near-perfect medium for reviewing a mission before leaving the base. Soldiers draw roads, buildings, bridges, anything that may lie along the route. They plan approaches. They look for likely ambush sites. Commanders can throw out changes — the third vehicle breaks down here – and talk through how to handle them.

Thursday’s sand table preceded a much nastier course on IEDs, improvised explosive devices, than what the soldiers faced Wednesday. They trained Wednesday on a static course. The explosion came at the same place each time. They moved to a 29-mile loop for Thursday’s training. The loop had multiple villages, each one of which is a potential ambush waiting to happen.

That uncertainty has advantages in training. It’s more realistic. Insurgents don’t give American soldiers the schedule for attacks each morning. They don’t attack from the same place every time.

The soldiers listened intently, their weapons slung in front of them. Most took notes as the company leaders went over specific points.

“You all remember the roundabout?” asked a lieutenant. The soldiers nodded. “We need to own that.”

Almost everything seemed to be the same color as the sand. The tents blend in. The roads aren’t gravel so much as they are packed yellow dust with small rocks. A steady wind kicked the dust into the air, turning even the air yellow.

There were spots of incongruous beauty. A monarch butterfly landed near the table. Its bright orange wings stood out sharply.

Lt. Col. Thomas Vickers came over to check on the soldiers. He’s higher on the chain of command and he’s responsible for soldiers from six states. Vickers spoke with a light Alabama drawl as he described the situation. He sounded like the football coach he is in civilian life.

“Iowa sent us a good unit,” he said. “I think we’ve integrated pretty well together.”

Vickers knows the 833rd has a critical job. Three thousand trucks use the main road from Kuwait to central Iraq every day. The Iowa soldiers must keep it open.

The command tent was casual over lunch. They ate MREs, an acronym that stands for “Meal, Ready to Eat.” There are many less flattering terms for the food. Most soldiers agree the Army has worked to improve them, but mass produced anything gets repetitive in a hurry.

A simulated mortar attack interrupts. The soldiers throw on their Kevlar armor and strap down their helmets before going outside. The virtual bunker is alongside the tent.

Several soldiers carry part of their lunch with them. Nobody is rushing. They move with deliberate speed. They aren’t lax. They aren’t rattled, either.