RT Journal Article SR Electronic T1 Abstract JF Arboriculture & Urban Forestry (AUF) JO JOA FD International Society of Arboriculture SP 184 OP 184 DO 10.48044/joa.1991.17.7.184 VO 17 IS 7 YR 1991 UL http://auf.isa-arbor.com/content/17/7/184.abstract AB