TY - JOUR T1 - Summer Branch Drop JF - Arboriculture & Urban Forestry (AUF) JO - JOA SP - 111 LP - 113 DO - 10.48044/jauf.1983.028 VL - 9 IS - 4 AU - Richard W. Harris Y1 - 1983/04/01 UR - http://auf.isa-arbor.com/content/9/4/111.abstract N2 - Apparently sound limbs occasionally break out of mature trees during calm summer weather. Species of at least 19 genera are susceptible. This is particularly puzzling since normally limbs would be lighter in weight during times of high transpiration. High xylem pressure and/or weakening of the cell wall bonding in the xylem accompanied by increased limb weight may be responsible. ER -