The soybean cyst nematode (Heterodera glycines, SCN) causes many millions of dollars worth of damage to Kentucky soybean fields each year. This occurs even though damage is mostly preventable and controls are inexpensive. This situation exists because a large number of soybean producers are unaware that cyst nematode is damaging their crops. In most cases soybean cyst nematode will cause significant yield reductions without producing any detectable symptoms in soybeans. When symptoms do occur, they are frequently thought to be associated with some other factor, such as soil compaction or low soil fertility.