This Is AuburnElectronic Theses and Dissertations

Stem Cutting Propagation of the Endangered Species, Clematis socialis (Kral)




Johnson, Connie

Type of Degree





Clematis socialis (Kral), the Alabama leather flower, is a federally listed endangered species native to NE Alabama and NW Georgia. In addition to conservation and management practices of the few existing populations, knowledge of this species’ reproduction is needed to aid in establishing additional populations needed to remove it from the endangered species list. Considering all methods used in clematis propagation, past and present, stem cuttings appear to be the most feasible method to obtain a large number of propagules in a relatively short amount of time without significantly disturbing native or established plants. However, there is little information about the cutting requirements of C. socialis. In one experiment, C. socialis stem cuttings were stuck in non-amended sand, perlite, vermiculite, and 1:1:1 (by volume) sphagnum peat moss: pine bark: sand (P:PB:S) to compare the efficiency of each substrate in rooting. Sand, the industry standard, perlite and vermiculite all performed similarly and better than the P:PB:S substrate in 2000, 2004, and 2005. Rooting percent averages were highest in sand and perlite in all three years, and cuttings in these two substrates were the earliest to root in 2005; approximately two weeks earlier than those in vermiculite. Although vermiculite’s root initiation was later than in sand and perlite, some of the highest root length, root number, and root rating averages were observed in it. Sand’s consistent high performance, early root initiation, availability, and lower cost per cutting makes it the most suitable substrate for rooting C. socialis stem cuttings. In a second experiment, C. socialis stem cuttings were stuck in a 2:1:1 (by volume) sphagnum peat moss, pine bark, and perlite substrate amended with rates of dolomitic limestone ranging from 0.0 to 12.5 lbs/yd3. Average root length, root number, and root rating increased linearly as dolomitic limestone amendment rate increased in all years, while rooting percent and cutting survival improved as lime rate increased only in 2004. Optimal rooting and root growth were obtained using lime rates between 10 to 12.5 lbs/yd3. Since there were also quadratic responses in many instances, using rates higher than 12.5 lbs/yd3 would not appear to yield better results. In a third experiment, C. socialis stem cuttings were stuck in 1:1:1 (by volume) sphagnum peat moss: pine bark: perlite amended with 10.0 lbs/yd3 dolomitic limestone to compare the efficiency of growth regulator treatments from 0/0 ppm IBA/NAA [indole-3-butyric acid (IBA)/naphthalene acetic acid (NAA)] up to 7500/3750 ppm IBA/NAA on rooting. Results indicated that growth regulators were not necessary to initiate rooting but that rates between 4500/2250 ppm IBA/NAA and 6000/3000 ppm IBA/NAA initiate rooting earlier. Rooting percent and root growth was generally highest between 3000 to 4500 ppm IBA and 1500 to 2250 ppm NAA.