Narrative:

I was giving a private pilot instruction in short and soft field operations, when he stated he would like to land on a grass strip. We proceeded to easton valley view at greeley county, a 5000 ft long dirt/grass strip. On final approach, I noticed a tractor working the strip on the south side. I thought I would let the student make the go around choice but he seemed intent on landing, so, at approximately 100 ft AGL, I called for a go around. He had full flaps and descended another 50 ft before getting the aborted landing going. We flew by the tractor at a safe altitude, and climbing, but I realized I had compromised safety by letting a less experienced pilot carry the approach too far in his eagerness to land on the unimproved runway. In the future, I will not let inexperienced pilots delay a go around until it becomes critical. I will call the action and explain the need later.

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Original NASA ASRS Text

Title: LOW ALT GAR PERFORMED TO MISS OBSTRUCTION ON GRASS STRIP. OBSTRUCTION TRACTOR VEHICLE. NON TWR ARPT NON UNICOM.

Narrative: I WAS GIVING A PVT PLT INSTRUCTION IN SHORT AND SOFT FIELD OPS, WHEN HE STATED HE WOULD LIKE TO LAND ON A GRASS STRIP. WE PROCEEDED TO EASTON VALLEY VIEW AT GREELEY COUNTY, A 5000 FT LONG DIRT/GRASS STRIP. ON FINAL APCH, I NOTICED A TRACTOR WORKING THE STRIP ON THE S SIDE. I THOUGHT I WOULD LET THE STUDENT MAKE THE GAR CHOICE BUT HE SEEMED INTENT ON LNDG, SO, AT APPROX 100 FT AGL, I CALLED FOR A GAR. HE HAD FULL FLAPS AND DSNDED ANOTHER 50 FT BEFORE GETTING THE ABORTED LNDG GOING. WE FLEW BY THE TRACTOR AT A SAFE ALT, AND CLBING, BUT I REALIZED I HAD COMPROMISED SAFETY BY LETTING A LESS EXPERIENCED PLT CARRY THE APCH TOO FAR IN HIS EAGERNESS TO LAND ON THE UNIMPROVED RWY. IN THE FUTURE, I WILL NOT LET INEXPERIENCED PLTS DELAY A GAR UNTIL IT BECOMES CRITICAL. I WILL CALL THE ACTION AND EXPLAIN THE NEED LATER.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.