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Canada yew (Taxus canadensis Marsh.) is a native evergreen shrub found in most of Ontario that contains anticancer compounds called taxanes in its needles, bark, and roots. In 2004, a research project was initiated to (i) develop methods for selecting individual yew plants with high growth rates and high taxane concentrations, and (ii) determine the best methods for growing Canada yew in plantations, towards the goal of developing the capacity to produce a commercially viable yew crop in northern Ontario. Four plantations were established in the Algoma district of Ontario; one in June 2004 at the Ontario Forest Research Institute (OFRI) arboretum and three in late August 2005 at the OFRI arboretum, Thessalon First Nation BioCentre, and Wheian farm. Treatments imposed on all the plantations were (1) crop plant spacing at 30 and 45 cm, (2) soil treatments of mulch, fertilization, and mulch-plus-fertilization. Compost and mulch-plus-corn post treatments were applied only on the 2004 plantation. Compared to the controls, only the 2004 plantation showed significant treatmentrelated increases in growth in all but the spacing treatments, with fertilization and mulch-plus-compost resulting in about 15% to 50% more growth, respectively, than the other treatments. Fertilization provided the most cost effective increase in yew plantation growth. Deer browsed the plants at all sites and, of the three herbivore control measures attempted, only the electric fence successfully excluded deer. Selection of individual yew plants for high growth rates and taxane concentrations yielded individuals with 3 to 4 times the potential taxane production capacity of the average plant. Further development of Canada yew as a value-added crop will require these high taxane-producing individuals to be propagated for plantation culture.
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