Northern Leaf Blight and Gray Leaf Spot have been seen in corn for years. Syngenta Agronomic Service Representative Dean Grossnickle says Tar Spot is a disease that also deserves attention. Once established in a field, Tar Spot can move very quickly. “You walk by a green leaf with a dark speck on it and it doesn’t stand out. Unless, you’re really looking closely at that it can fool you.” Grossnickle says farmers need to be proactive with Tar Spot. “It goes so fast; if we spray the fungicide too late, I’m not sure we can recoup that yield back.” Fungicide application is recommended just as the corn crop begins to pollinate.
