DEVELOPMENT OF WOUND TISSUE IN THE BARK OF FRASER FIR AND ITS RELATION TO INJURY BY THE BALSAM WOOLLY ADELGID¹

A total of 89 Fraser fir, Abies fraseri Pursh. (Poir.), from seven locations in the southern Appalachians were tested for non-suberized impervious tissue (NIT) at artificial wound sites. All trees except one formed NIT in a time period that was considered normal (3 weeks), with no delays due to tree age, location or presence of balsam woolly adelgid, Adelges piceae (Ratz.). Although most Fraser fir react to adelgid attack by forming “rotholz” (red wood), a number of infested trees showed no visual signs of rotholz formation.