Nursery Field Fertilizer Evaluations in Ontario and Ohio

The green movement in the United States has forced examination of past practices to determine whether they are environmentally sound and based on scientific research. Fertilization practices by the green industry need to be examined closely to insure that growers are using nutrients in the most efficient and environmentally friendly method.  Twelve fertilizers or practices were tested at two cooperating nurseries in Ontario, Canada (Connon AVK, Christie Farm, West Flamborough, ON and Braun Nurseries, Fiddler’s Green Farm, Anacaster ON), one in Ohio (Sunleaf Nurseries, Madison, OH) and one test site at Ohio State University (Waterman Farm, Columbus, OH).  Tree liners of three species Acer rubrum ‘Red Sunset’ or Acer rubrum ‘Embers’ (Connon AVK), Pyrus calleryana ‘Chanticlair’ (at all sites) and Quercus rubrum were planted in mid May, Ontario, late April, 2009, Ohio to be grown for three years. Not all 12 fertilizer treatments, with exception of the Anderson products, were evaluated at all sites.  The fertilizers evaluated are field dry-soluble (standard practice) of 100#/ac granular 19-19-19 supplied by The Andersons, CRF’s: Osmocote 33-3-6, Osmocote 22-3-8 (The Scott’s Co. LLC, Marysville, OH), Polyon 36-3-6, Polyon 20-6-13 (Agrium Advanced Technologies, Brantford, ON), Anderson DG 9135, 23% and Anderson 9136, 33% (The Andersons Turf and Specialty Group, Maumee, OH), Acer 23-4-9, Acer 34-5-5, (Plant Products Co. Ltd., Brampton, Ontario), 50# fertilizer June and 50# in September at Connon AVK as a conventional practice and liquid feed as a conventional practice at Sunleaf Nurseries as farm grade, bulk, 100 # liquid UAN 28% and 100 # potash granular.  All fertilizers were applied to deliver 100 # N/ac/ to be distributed in a 9 sq ft² area around each tree.  Over location and species the two Anderson fertilizer tested were not significantly different from one another and tested as well as industry standards of Polyon and Osmocote.  In this first year of study growth was enhanced with 100 lb. N applications versus no fertilizer.  No fertilizer had more detrimental effects on maple growth over location.  The Osmocote 22-3-8, Polyon 20-6-13 and the Acer 23-4-9 were the only fertilizers that contained minors and were the treatments that produced the greatest increases in caliper.