Spring arrives next Wednesday — and so does the chance of meeting a slow-moving farm vehicle on a rural Iowa road. The Iowa Department of Transportation is putting out its annual warning for motorists to be especially cautious at this time of year.Scott Falb, a traffic safety specialist at the Iowa D-O-T, says farm vehicles were involved in 207 crashes statewide during the year 2000. Of those accidents, 108 involved property damage, 93 resulted in injuries and six brought deaths. Falb says farmers need to follow the rules of the road and motorists need to keep their cool. He says we expect to speed down the roadway, but you have to slow down and take it easy when there’s a slow vehicle on the road.Falb says D-O-T statistics teach lessons for both motorists and farmers.Most crashes occur when motor vehicles are going over the crests of hills or if they’re approaching a left-turning farm vehicle. The most common time of the day for collisions is between 4 P-M and 8 P-M. Those times may coincide with the period when commuter traffic is coming home from work and farm operators are returning from their fields.