PT - JOURNAL ARTICLE AU - John A. Weidhaas, Jr. TI - Goals And Hurdles For Shade Tree Programs AID - 10.48044/jauf.1976.044 DP - 1976 Sep 01 TA - Arboriculture & Urban Forestry (AUF) PG - 176--180 VI - 2 IP - 9 4099 - http://auf.isa-arbor.com/content/2/9/176.short 4100 - http://auf.isa-arbor.com/content/2/9/176.full SO - JOA1976 Sep 01; 2 AB - McIntosh, D.L (ed). 1975. Proceedings of the 1974 APDW workshop on crown rot of apple trees. Canadian Plant Disease Survey 55: 109-116.At a workshop sponsored by the Apple and Pear Disease Workers and held at Summerland, British Columbia, 16-17 August 1974, participants from the USA, UK, Poland, and Canada considered problems associated with collar rot of apple trees incited chiefly by Phytophthora cactorum. Topics included pathogens, symptomatology, methods of isolating P. cactorum, evaluation of resistance, pathogenic variation in P. cactorum, cultural practices and pre-disposition, control, ecological studies, and areas requiring further research.