Northwest Iowa firefighters were busy Monday with grass fires.Monday morning they fought one north of Rock Valley, that damaged a chicken confinement. Monday night, crews from Rock Valley and Rock Rapids joined local firefighters in Doon where a controlled burn got OUT of control. Around 3-30 this morning, the Rock Valley department was called to another grass fire near the north edge of town. Winds up to 40 MPH hampered work in all three fires. Nobody was hurt.