RT Journal Article SR Electronic T1 a Survey to Determine the Leaf Nitrogen Concentrations of 25 Landscape Tree Species JF Arboriculture & Urban Forestry (AUF) JO JOA FD International Society of Arboriculture SP 152 OP 159 DO 10.48044/jauf.2001.017 VO 27 IS 3 A1 Perry, Ed A1 Hickman, Gary W. YR 2001 UL http://auf.isa-arbor.com/content/27/3/152.abstract AB A survey was conducted to determine the concentrations of leaf nitrogen in 25 landscape tree species. Leaf samples were taken from mature, healthy trees in the landscape and analyzed for percent (total) nitrogen. Concentrations ranged from 1.0% (dry weight basis) for deodar cedar (Cedrus deodara) and Southern magnolia (Magnolia grandiflora) to 3.6% for white mulberry (Morus alba). The leaf nitrogen levels determined by the current study were compared to two other published surveys. From a practical standpoint, the list of tree species and their corresponding minimum leaf nitrogen values from visually healthy trees will allow arborists and landscape maintenance professionals to more effectively use leaf analysis for diagnosing nitrogen deficiency. The information can also be used for designing fertilizer programs, much as critical leaf nutrient level guides are currently used in the fruit and nut tree industries.