The wet spring and variable growing conditions this year have resulted in many uneven corn stands. These problems often can be attributed to poor root development, fungal root infection, or occasionally, moisture stress. But every summer there are instances of unthrifty corn growth throughout Iowa with no apparent cause. A possible explanation for the poor corn growth that probably is not considered very often is damage due to plant-parasitic nematodes. There are many species of nematodes that can damage corn.