Known Distribution of the Soybean Cyst Nematode (SCN) in the United States and Canada from 1954 to 2017

Distribution of SCN in 2017

by Greg Tylka and Christopher Marett, field crop nematologists, Iowa State University

The soybean cyst nematode, Heterodera glycines, (SCN) remains a major yield-reducing pathogen of soybeans. As an introduced pest, knowledge of the distribution of SCN can be helpful in identifying areas where scouting and management efforts should be focused. Such information is especially important for SCN because yield-reducing infestations can occur without obvious above-ground symptoms.

Maps identifying known SCN-infested counties in the U.S. and Canada have been compiled since the 1950\&\#39\;s. Heterodera glycines has now been found in every soybean-producing state in the United States except West Virginia. Since the last update of the map in 2014, H. glycines was discovered for the first time in 37 counties in 17 states, namely Alabama, Georgia, Indiana, Iowa, Kansas, Kentucky, Minnesota, Missouri, Nebraska, New Jersey, New York, North Carolina, North Dakota, Ohio, South Dakota, Virginia, and Wisconsin. Read the full article in Plant Health Progress.

Fall is often the best time to sample soil for soybean cyst nematode as you plan for the next crop year
Samples can be collected from harvested cornfields that will be cropped to soybean in 2018 in order to check if SCN is present. Collect samples from harvested soybean fields and check for SCN if yields were disappointingly low this year with no apparent cause.

Results of soil samples collected from fields with known SCN infestations will provide feedback on how well management practices have been working at keeping SCN numbers in check. University Extension personnel and publications can help explain your test results and make management recommendations based on those results.

SCN sampling and management resources
Soybean Cyst Nematode - Scouting (on this website)
Interpreting SCN Soil Sample Results - Iowa State University
SCN Management Guide 5th edition - NCSRP
Soybean Cyst Nematode Management Guide -University of Minnesota
Soybean Cyst Nematode Field Guide, 2nd edition, Iowa State University. Order a print edition fromISU Extension Online Store.