RT Journal Article SR Electronic T1 Allelopathic Effects of Kentucky Bluegrass on Northern Red Oak and Yellow-Poplar JF Arboriculture & Urban Forestry (AUF) JO JOA FD International Society of Arboriculture SP 281 OP 283 DO 10.48044/jauf.1988.067 VO 14 IS 11 A1 Kolb, T.E. YR 1988 UL http://auf.isa-arbor.com/content/14/11/281.abstract AB Allelopathic effects of Kentucky bluegrass (Poa pratensis) on seedling growth of northern red oak (Quercus rubra) and yellow-poplar (Liriodendron tulipifera) were investigated. Foliage extracts and leachates from potted Kentucky bluegrass did not reduce the growth of either species in a Hagerstown top soil over a 139-day period from seed germination. Removal of northern red oak cotyledons at the one-flush stage reduced growth of the stem and root, but did not affect susceptibility to bluegrass foliage extractives and pot leachates. The results suggest that previously reported detrimental interference between Kentucky bluegrass and seedlings of northern red oak or yellow-poplar can be attributed to competition rather than allelopathy.