It is easy to see obstacles in a field during tillage and planting, but they might not be visible in the mature crop. Large stones and stumps can cause upsets, especially on slopes. So remove as many obstacles as possible before harvest, and mark any others with a tall pole or stake so they can be seen clearly in the mature crop. Ditches pose special problems. A safe distance from ditch edges at planting time may not be safe at harvest because of the difference in size and weight of planting and harvesting equipment.
Heavy rains can also undercut banks or form new ditches.
Plant crop to allow extra turning space near ditches, and double check for undercut embankments and new ditches before harvest. In general, allow at least one-fourth more turning space than required by the largest piece of equipment you will be using. A good weed control program will improve crop quality and reduce plugging of harvest equipment. Adjusting and Servicing Combines For safety and efficiency, service machinery before beginning the day's work, and as needed during the day. Before working under a header, be sure the header latch is fixed in place or that proper blocking is used.