PT - JOURNAL ARTICLE ED - , TI - Abstract AID - 10.48044/joa.1981.7.7.187 DP - 1981 Jul 01 TA - Arboriculture & Urban Forestry (AUF) PG - 187--187 VI - 7 IP - 7 4099 - http://auf.isa-arbor.com/content/7/7/187.short 4100 - http://auf.isa-arbor.com/content/7/7/187.full