It causes sharply demarcated grey blotches consisting of many small black flyspeck like dots. In 2003, Hales started work on Flyspeck to vindicate his proof of the Kepler conjecture. Flyspeck disease is caused by Schizothyrium pomi. In August 2014, the Flyspeck team's software finally verified the proof to be correct. Flyspeck frequently occurs in older trees with light colored peels (Golden Delicious, etc.).