American Yew is a low evergreen shrub with many branches that are spreading or ascending and sometimes prostrate, rarely over 5 feet high. Branches tend to spread horizontally for 2/3rds of their length before curving upward.
Bark is thin, scaly and reddish-brown with age.
Twigs are green to yellow-green when young
The leaves (Needles) are dark green upper and lower sides, attached singly, flattened with pointed tips (but not sharp). The attachment point is also pointed. They are attached all around the twig in a spiral pattern but bend around such that they give a flattened appearance to the twig with the leaves projecting laterally but not up and down. They are 3/8 to 1 inch in length with the midrib slightly elevated. Two stromatal bands exist on the underside of the needle.
Flowers: The genus is a gymnosperm and thus lacks true flowers and instead has sporophylls that produce pollen sacs. American Yew is usually monoecious (unlike most members of the genus) bearing both male and female sexual parts, but in separate structures separated on the branches. However, this is variable and under certain conditions the species becomes dioecious where smaller plants tend to be male. When monoecious, the female parts outnumber the male parts (male parts are known in yews as 'stroboli'). The male parts are small cone shapes appearing as stalked heads. Female cones are smaller, beginning as pointed buds and subtended by a series of small bracts.
Seed (Cones): After pollination the female flowers become a 1/2 inch diameter fleshy, red, berry-like cone (an aril) containing the seed which ripens in mid to late summer. The cone is open at the top and the top of the brown flattened seed is visible.
Toxic: The seeds and foliage are toxic to humans and livestock but not too wild browsers who love it especially white-tailed deer in the winter time. The red fleshy pulp surrounding the seed is not considered so toxic.
Habitat: American Yew is an understory shrub, highly preferred by white-tailed deer and moose. It grows best in partial shade in well drained soils with a pH between 5.0 and 7.5, and cooler temperatures as it is a northern plant.
Names: The genus, Taxus, is from the Greek taxos, referring to the yew plant. The species name, canadensis, means 'of Canada'. The name of the plant classification author, ‘Marshall’ is for Humphry Marshall (1722-1801), American Botanist, who published in 1785 - Arboretum Americanum: The American Grove, an Alphabetical Catalogue of Forest Trees and Shrubs, Natives of the American United States.
Comparisons: The only similar species is T. cuspidata, the Japanese Yew, which has broader leaves and is found only in cultivated settings and is not as straggly looking.
Above: Shrub photo ©Derek Anderson, University of Wisconsin.
Below: Photo of pollen cones ©Matthew Wagner, University of Wisconsin. Flowers develop into the unique looking red cone called an 'aril'.
Below: 1st photo - needles grow all around the twig but twist to one side and appear as two flattened rows. 1nd photo - older bark is scaly with reddish undertones.
American Yew is a native species, ranging in North America from Manitoba, Minnesota and Iowa eastward to the coast and south as far as Tennessee and North Carolina. In Minnesota it is found primarily in the northern 1/3 of the state, and then south along the St. Croix valley and along the Mississippi River to Iowa with the exception of Goodhue county. It is not native to Hennepin County where the Garden is. It is the only species of Taxus and only member of the Taxaceae family native to Minnesota. The species is on the "threatened list" in a number of eastern states.
Eloise Butler introduced the species to the Garden when she planted it on May 19, 1909 - sourced from the Park Board Nursery. She planted again in 1911, 1916, and in Sept. 1919 with 3 from Lutsen, MN. Martha Crone planted the species in 1936, '41, '48, '56, and '57. Most yew species used in landscape plantings are varieties of the species T. baccata, the English Yew.
Lore and uses: Densmore (Ref. #5) in her study of the Minnesota Chippewa reports being told that little twigs of this species, boiled together with twigs of Eastern Redcedar, Abies balsamea, would produce a decoction to alleviate the pains of rheumatism. It could be either taken internally or the decoction would be sprinkled on very hot stones and the "patient" being closely covered, would let the steam from the decoction warm the rheumatic joints - especially the knees. In modern times the foliage and green stems are used to extract a white crystalline powder called paclitaxel, which is used as an anti-cancer drug. It was first isolated in 1971 from the Pacific Yew and approved for medicinal use by various countries in the 1990s. All Taxus species produce this. Due to limits on the natural availability of the species, a cultured version has been developed. (Fischer J, Ganellin CR (2006). Analogue-based Drug Discovery. John Wiley & Sons.)
References: Plant characteristics are generally from sources 1A, 32, W2, W3, W7 & W8 plus others as specifically applied. Distribution principally from W1, W2 and 28C. Planting history generally from 1, 4 & 4a. Other sources by specific reference. See Reference List for details.
Identification booklet for most of the flowering forbs and small flowering shrubs of the Eloise Butler Wildflower Garden. Details Here.
Friends of the Wild Flower Garden, Inc. Text and photos are by G. D. Bebeau unless otherwise credited. "www.friendsofthewildflowergarden.org"