The oak leaftier, Croesia semipurpurana , and the oak leafroller, Archips semiferanus , are important Tortricidae moths in a complex of native species feeding in the early spring on oak foliage throughout the forests of Eastern North America.
Outbreaks periodically develop with frequent and severe defoliation resulting in tree mortality.
The last outbreak during the 1960's and 1970's covered large areas of Connecticut, Massachusetts, New York, Pennsylvania, Virginia, and West Virginia. Either moth species may dominate during an outbreak depending upon which oak species are present. Resting adults of both species hold their wings in a characteristic bell shape. Adults of both species are distinctly marked. Newly hatched oak leaftier larvae enter opening buds and eat immature leaves.