RT Journal Article SR Electronic T1 Abstract JF Arboriculture & Urban Forestry (AUF) FD International Society of Arboriculture SP 34 OP 34 DO 10.48044/joa.1977.3.2.34 VO 3 IS 2 YR 1977 UL http://auf.isa-arbor.com/content/3/2/34.abstract AB