Using RFID for Inventory Tracking in Container and Field Nursery Operations

Radio frequency identification (RFID) tags were used to track bare-root harvested nursery trees at a wholesale nursery, J. Frank Schmidt and Son Inc. (JFS), as they were loaded into transport pallets and to track pallet movement during transport on a flatbed tractor-trailer. Harvested trees were graded by size, tied in bundles, labeled with RFID tags and loaded into wooden pallets in a warehouse.  The pallets were 1.22 m x 2.44 m, with walls along the long sides at 1.22 m height and the short side without walls. An Alien ALR 9900 RFID reader was connected to 2 MTI MT262006 and 2 Laird 9025PR antennae. Two antenna layout patterns were used to read the RFID tags and evaluate antenna placement on read success. Three pallet load densities (bundles per pallet) were evaluated. There were 10 trees per bundle for medium and high density loads and 3 or 5 trees per bundle for low density loads. The number of tags read was compared to number of tags used, a manual count by the JFS crew, and a manual count by the research team. Manual miscounts occurred for all pallet densities. No tags were missed by the RFID system for pallets with less than 48 bundles. For pallets with 54 or more bundles, there was an average of 1.5 tags per pallet missed. A total of 841 tags were used between all densities. Accuracy was similar for all methods with 9, 11, and 8 tags missed by the RFID system, JFS crew, and research team, respectively. Antenna location and type affected tag counts with the best results achieved from overhead placement using the MTI antenna. One plastic encased RFID tag was attached to each of two pallets, the pallets placed on a tractor-trailer and driven past an antenna array with the tags on the same side and repeated with the tags on the opposite side of the antennae. One of each antenna was placed at 2 m and 3 m. The antennae placed at 3 m read both pallets for each of 3 passes by the truck while at the 2 m placement only the MTI antenna read one pallet on one pass. The effectiveness of RFID in reading tags in a container yard with the same type of slip-on tags will be evaluated this spring and presented as well.