east to west). The vigor of individual trees varied greatly and the majority of those sampled were under six feet tall. The number of cuttings harvested varied with each tree depending on the overall health of the specimen. As few as one and as many as 82 cuttings were taken per plant with the average being 15.79. Each collection from each genotype was given an accession number at the time of collection and this number followed the plant through the propagation cycle. A metal label bearing this number was affixed to the parent tree. Cuttings were taken in November 1989 and were transported to greenhouses in Massachusetts, where they were given a fungicide soak (Zyban) and subsequently propagated.
    Previous trials with Torreya cuttings (Nicholson, 1987) had experimented with various rooting hormones and hormone strengths and had produced a topmost rooting percentage of 65%. In an attempt to increase this percentage, different rooting media were compared and the hormone strength was doubled from 5000 ppm Indolebutyric Acid (IBA) to 10,000 ppm IBA in 50% EtOH. A total of 666 cuttings from 45 different genotypes had the bottom 4 cm of needles removed from the stems, were given a fresh cut, and the basal portions were immersed in the 10,000 ppm IBA solution for five seconds. These were then stuck under a poly tent in a medium of coarse builder's sand and medium grade perlite (1:1 by volume) with a bottom heat of 75 degrees F. One thousand eight hundred and forty-eight cuttings from 121 different genotypes were treated in the same manner, but a rooting medium of #10 grade crushed pumice, shredded peat moss, and medium grade perlite (6:2:1 by volume) was used. Cuttings were evaluated after six months and potted on. Rooting percentage of those cuttings stuck in the sand/perlite medium was 79.2 percent while those cuttings stuck in the pumice/peat/perlite mix rooted at a percentage of 90.8 percent.
    Roots were measured and counted for all cuttings stuck in the sand/perlite mix and for an equivalent number of randomly selected cuttings from the pumice mix.

 
 
Copyright July 1998
Public Garden
The Journal of the American
Association of Botanical
Gardens and Arboreta
Vol. 13, No. 3
Rooted Cuttings
  Rooted cuttings

A total of 1332 cuttings were analyzed. Recorded were:

 number of primary roots (roots
    originating from the stem);

 longest root length; and

 total number of root tips
    (primary and branch roots);

 cumulative length of roots.

    The cuttings rooted in the sand/perlite mix produced an average of 2.90 main roots and 3.44 total root tips. The longest root length averaged 6.37 cm with an aggregate root length averaging 12.98 cm. Highest values recorded for each category were 13 primary roots, 13 total root tips, 14 cm greatest length, and 42 cm aggregate length.
    The cuttings rooted in the pumice mix produced an average of 2.40 primary roots per cutting and 5.09 total root tips. The longest root averaged 10.26 cm with an aggregate length averaging 16.92 cm. Highest values recorded for each category were 10 primary roots, 18 total root tips, 22 cm greatest length, and 49 cm. aggregate length.
    A comparison of these two media showed that the pumice mix yielded a higher percentage of rooted cuttings, and a more highly branched root system of greater total length.
  Cuttings were potted and grown for two years and then shipped to botanic gardens and biological institutions worldwide for observation and research. Institutions receiving plants were the Arnold Arboretum of Harvard University; Bok Tower Gardens; Royal Botanic Garden, Edinburgh;

Illinois Natural History Survey; Mercer Arboretum; North Carolina Botanic Garden; Tall Timbers Research Station; USDA Forest Service, Berkeley; and USDA Forest Service, Gulfport.
    Of particular note is the collaboration between The Botanic Garden of Smith College and the Atlanta Botanical Garden. Cuttings sent to the Atlanta Botanical Garden were raised in containers and by 1997 some had grown to five feet and had begun to set seed. A nursery mix of 15 parts composted pine bark mulch, one part granitic sand, and amendments of lime, bone meal, and cow manure proved to be an excellent growing medium, and the plants were grown outside under 50 percent shade. Fertilization was provided by high nitrogen 17-6-12 Osmocote, applied at half strength twice a year. If the plants looked peaked, additional fertilization was by 20-10-20 liquid feed.
    All plants were labeled as to original locale. In 1997 these plants were the source of additional cutting material. More than 4,000 cuttings representing 150 genotypes were installed at The Botanic Garden of Smith College. Once rooted, these will be transported to the Atlanta Botanical Garden where a distribution to other botanic gardens, agricultural stations, colleges, nature reserves, and state parks in Georgia is envisioned.
    The partnership between our two gardens, both with a strong emphasis on conifers, has proven to be a great success, and plans are being formulated to further develop this collaboration.

Discussion
    Reintroduction of documented Torreya taxifolia germplasm into the original collection areas within the native range is the most logical goal of the ex situ program, and a multidecade or multigenerational approach probably is needed. The microclimate or ecosystem of the ravines may have been irrevocably altered and Torreya taxifolia may no longer be able to survive within this new environment. The success of an ex situ program is, in itself, no guarantee that successful reintroduction can occur. However, it is a necessary approach given the ongoing decline of wild stands.
    Thought also must be given to the best type of propagules with which to attempt reintroduction of the species. Dr. Mark

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