Heller’s japanese holly was selected as a seedling in 1934 by J. Heller, manager of Newport Nursery (Newport, RI), and was named and introduced into the nursery industry in the late 1930s. This dwarf cultivar grows to 2 ft high and 4 ft wide with a dense mounding habit. Popular in landscape situations where a dwarf plant is needed, Heller’s japanese holly is considered the standard by which other dwarf cultivars are judged (Galle, 1997).
Heller’s japanese holly can be used in full sun or partially shaded settings (Berry, 1994; Gilman, 1999). Plants are readily grown and maintained in the landscape, provided soils are not too dry or too wet (Berry, 1994), and are recommended for landscapes in U.S. Department of Agriculture (USDA) hardiness zones 5b to 8a (Gilman, 1999). Plants are grown primarily for their form and foliage; fruit is rarely produced (Gilman, 1999). Heat can be a limiting factor in nursery production of this crop (Berry, 1994).
An auxin treatment is typically recommended to promote adventitious root formation on stem cuttings of Heller’s japanese holly (Berry, 1994; Dirr and Heuser, 1987). Stem cuttings of other hollies, including ‘Dwarf Burford’ holly (Ilex cornuta), ‘Nigra’ inkberry (Ilex glabra), and dwarf yaupon holly (Ilex vomitoria ‘Nana’) can be successfully propagated from winter cuttings without the use of an auxin treatment (Blythe and Sibley, 2007, 2009; Blythe et al., 2004).
Elimination of unneeded steps is critical to improving nursery production processes (Blythe and Sibley, 2001). Baldwin and Stanley (1981) noted treatment of cuttings with auxin to be one of several nursery operations that merit attention. Even small, but meaningful, changes made over time can improve processes and eliminate waste in nursery operations, all in keeping with the principles of “lean flow” management which has been adopted by a variety of businesses and institutions (Epps, 2009). The objective of this study was to determine whether winter stem cuttings of Heller’s japanese holly could be propagated without use of a conventional basal quick-dip in auxin, thus eliminating one step in the cutting propagation process and reducing chemical use.
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