Some specialists believe that the injury is caused by cold temperatures after the bud has broken dormancy but before it opens. This year, the tatters affected mostly white oaks plus a few bur and black oaks. This year the tatters was also accompanied by cupping and blackening of the ends of some leaves which may have been caused by frost. Individual trees and groups of trees were affected. In some trees damage was more severe in the upper than in the lower crown.
Damaged trees range in size from mature to ankle-high seedlings.
Most trees produced a second crop of foliage. Balsam Fir Needle Diseases . Lirula mirabilis and Rhizosphaera pini , two needlecast fungi on balsam fir, were observed in north central and northeastern Wisconsin. Both of these fungi caused browning of the second and third year needles. These fungi have been documented as being present in Wisconsin's forests for many years yet their incidence has increased since 1994.