RT Journal Article SR Electronic T1 An Evaluation of Dormant Oil Phytotoxicity on Six Species of Woody Ornamentals JF Arboriculture & Urban Forestry (AUF) JO JOA FD International Society of Arboriculture SP 102 OP 105 DO 10.48044/jauf.1988.025 VO 14 IS 4 A1 R.W. Baxendale A1 W.T. Johnson YR 1988 UL http://auf.isa-arbor.com/content/14/4/102.abstract AB Conflicting reports concerning possible phytotoxicity of horticultural oils applied to woody plants in dormant condition prompted an evaluation of superior oil Sunspray 6E on six species of ornamentals. Young dormant saplings of pear, sugar maple, Japanese maple, European hornbeam, Scots pine and red pine were unaffected by oil concentrations of up to 8%. Bud break was neither reduced nor significantly delayed and no damage to bark or bud scales was observed at any concentration. Leaves developed normally when dormancy was broken with no twig dieback observed. Results show no phytotoxicity for this product even when applied at rates 4X the usually recommended concentration.