Stem cuttings were harvested in April from four clones of containerized bunchberry(Cornus canadensis L.) forced in the greenhouse and in June from the same four clones growing in the field. April cuttings that had produced rhizomes by transplant time produced the greatest mean number and weight of shoots during the first growing season compared to April cuttings without rhizomes, June cuttings with rhizomes, or June cuttings without rhizomes. In a second study, cuttings and single-stem divisions were taken in July; divisions produced a greater mean number of shoots than did stem cuttings when compared at the end of Oct. A third study evaluated the effect of K-IBA application to lateral buds on subsequent rhizome production, and the effect of cutting node number (two vs. three nodes) on root or rhizome development. Treating lateral buds with K-IBA was not inhibitory to rhizome formation and elongation. Compared to two-node cuttings, three-node cuttings produced greater mean rootball size, rhizome number, and rhizome length; nearly twice as many of the three-node cuttings formed rhizomes as did two-node cuttings. A fourth study showed that cuttings rooted for 5 or 6 weeks in a mist enclosure generally exhibited greater shoot and rhizome production by the end of the first growing season than cuttings rooted for 8 or 9 weeks. This was despite the finding that cuttings rooted for longer durations (8 or 9 weeks) possessed larger rootballs and greater rhizome numbers at transplant time compared to cuttings rooted for shorter durations (5 to 6 weeks). Chemical name used: indole-3-butyric acid (K-IBA).
Janine G. Haynes, John M. Smagula, and Paul E. Cappiello
Michael W. Smith and William D. Goff
certainty viable buds. Another possibility is growth inhibitors, such as abscisic acid, suppressing bud growth ( Tucker, 1981 ) although auxin inhibition of lateral buds was repressed. Additional growth-regulating chemicals might be beneficial to force