As advocated by Coates et al. (1994), thawed planting stock taken to the field should optimally be kept cool at 1 °C to 2 °C in relative humidities over 90% (Ronco 1972a). For a few days, storage temperatures around 4.5 °C and humidities about 50% can be tolerated. Binder and Fielder (1988) recommended that boxed seedlings retrieved from cold storage should not be exposed to temperatures above 10 °C. Refrigerator vans commonly used for transportation and on-site storage normally ‘maintain seedlings at 2 °C to 4 °C (Mitchell et al. 1980). Ronco (1972a, b) cautioned against using dry ice (solid carbon dioxide) to cool seedlings; he claimed that respiration and water transport in seedlings are disrupted by high concentrations of gaseous carbon dioxide.