Soybean cyst nematode (SCN) is an important, widespread soybean pest in Iowa that often goes unnoticed. To date, the nematode has been discovered in all but five Iowa counties. The only consistent and reliable sign of an SCN infestation in the field is the presence of adult SCN females and cysts (dead females) on the roots of infected soybean plants. Adult SCN females and cysts are small, round, and white to yellow, each approximately the size of a period at the end of a sentence.