"There you are," Ray said. "Same field isn't the same load, and same season isn't the same water. If the ground is hiding a weakness, new weight and a wet spring can make it show itself."
Tom searched for another explanation because the alternative seemed too strange. "What about a buried foundation? There's stories about a homestead somewhere on this side of the creek. Could be a rock nobody ever hit before."
Ray nodded. "That's sensible. We'll test it." He began from sound ground near the edge of the marked strip and pushed the long rod into the soil.
Under ordinary resistance it would meet a firm layer below the loose cultivated surface, but near the flagged area it descended farther than Ray expected with very little effort. He drew it back, tried a second location with the same precautions, and found the same difference. Several yards away, where the flags no longer lined up, the resistance returned at a more usual depth.
The rod was only a clue, Ray emphasized, not a measurement of the whole ground beneath them. A stone or foundation would produce resistance, while disturbed or washed-out earth could produce less, but the work of determining what lay below belonged to someone with the right equipment and experience. He stopped probing when the pattern was clear enough to justify caution. Tom wanted him to keep going, as if more holes might somehow eliminate the threat. Ray handed the rod back to his truck instead.
"A rock would've stopped that thing," Tom said, still looking at the soil.
"And it didn't. That's one theory we can move down the list." Ray scanned the strip. "Have you ever noticed a difference in crops here?"
Tom hesitated. The corn along this diagonal was often darker green and sometimes taller in early summer. He had congratulated himself on the quality of the soil without asking why one narrow band behaved differently. After rainfall, it could remain damp while the rest of the field dried enough to work. He remembered his father calling it the low strip, even though the surface barely changed elevation.
"Dad never liked equipment parked there," Tom said. "I figured he didn't want us making ruts. He used to tell me to take the service truck around the long way after a rain." A memory formed slowly: Harold standing near the old fence post with one arm raised, calling out to a hired man to keep the grain wagon on the firmer headland. Tom had been young and annoyed by the detour. He had never asked his father why it mattered.
Ray turned toward him. "Did Harold leave a drainage map?"
"He kept notes on everything."
"Then maybe he kept this."
Tom looked back at the farmhouse, beyond the low rise where the machinery shed stood. In the back of that shed was a green filing cabinet, dented along one side and covered with a decade of dust. It had belonged to Harold. Tom had not opened it since the weeks after the funeral, when even the smell of old paperwork had been enough to make him close the door again.