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Cephalotaxus Harringtonia (D. Don) C.H.E. Koch Japanese Plum Yew (Cephalotaxus Drupacea, Cephalotaxus Nana, Cephalotaxus Pedunculata, Cephalotaxus Sinensis)

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Cephalotaxus Harringtonia (D. Don) C.H.E. Koch Japanese Plum Yew (Cephalotaxus Drupacea, Cephalotaxus Nana, Cephalotaxus Pedunculata, Cephalotaxus Sinensis) Cephalotaxus harringtonia (D. Don) C.H.E. Koch Japanese Plum Yew (Cephalotaxus drupacea, Cephalotaxus nana, Cephalotaxus pedunculata, Cephalotaxus sinensis) Other Common Names: Cow’s Tail Pine, Harrington Plum Yew. Family: Cephalotaxaceae. Cold Hardiness: Useful in USDA zones 6 through 9 with the proper cultivar selection. Foliage: Evergreen; simple; alternate; narrowly linear; ¾O to 1½O (2 O) long; strongly two-ranked, arching upward then out and down; dark glossy green to blackish green with two bands of stomata underneath; tips acute to mucronate; leaves stiff, almost plastic-like in texture. Flower: Dioecious or rarely polygamo-dioecious; small pendant ovoid male cones are axillary, while the more conical females are stalked with two ovules per bract of which only one matures; pollen is shed in early spring. Fruit: Elongated ovoid olive-like drupes on female plants; green turning red-brown to brown at maturity; 1O to 1¼O long; not ornamental; fruit and foliage are reportedly poisonous. Stem / Bark: Stems — thick and stiff; glabrous; ridged and furrowed; green to yellow-green, may develop a reddish cast in winter; Buds — ovoid male and conical female cones developing from stalked buds; Bark — exfoliating in gray-brown to red-brown strips on older specimens. Habit: Plants are of variable shapes and sizes; most cultivars in our regional landscapes have been selected for a distinctively spreading or strongly erect habit, whereas the species varies between these extremes; in favorable locations plants may mature to the stature of small trees, 15N to 20N(30N) tall, but most specimens in our regional landscapes are medium shrubs 5N to 10N tall; overall plants are medium in texture. Cultural Requirements: Much easier to grow in our region than Taxus, but still not proving as tough as touted by various horticulturist in the rest of the Southeastern US; plants perform much better in East Texas than in Central, South and West Texas; although plants are capable of surviving in full sun in certain locations, use in our region should be limited to shady to semi-shady locations; although capable of tolerating some drought once established, C. harringtonia still needs regular moisture and rich well drained soils to look its best; plants readily tolerate shearing; salty irrigation water in College Station prohibits wide-spread use in our local area and specimens on alkaline clays in Dallas performed poorly; good specimens can be seen in Tyler and Nachogdoches. Pathological Problems: None of particular consequence; occasional spider mites in hot weather. Ornamental Assets: Very handsome dark lustrous green leaves resembling that of the Yews (Taxus spp.) or perhaps Japanese Yews (Podocarpus macrophyllus); generally not browsed by deer. Limitations & Liabilities: Vigor tends to be limited in Central and West Texas. Landscape Utilization: Japanese Plum Yews can be used as substitutes for the less heat tolerant Taxus spp. and the even slower growing Podocarpus macrophyllus var. maki as general purpose needled evergreen shrubs in our regional landscapes; plants can be allowed to develop a natural form or can be sheared into formal hedges and topiaries; this species is slow growing and functions as a shrub for an extended time in our regional landscapes. Other Comments: A much hailed species in the trade, but the key to success seems to be good growing conditions and shade in our region, else results can be disappointing; plants are a bit stiff and formal for my taste, but this works in certain settings. Native Habitat: Southeast Asia, including China, India, Japan, and Taiwan. Related Taxa: Considerable debate occurs as to the hierarchical status of several closely related taxa that are variously listed as varieties of C. harringtonia or given specific rank, including Cephalotaxus drupacea P.F. von Siebold & J.G. Zuccarini, Cephalotaxus nana T. Nakai, Cephalotaxus pedunculata P.F. von Siebert & J.G. Zuccarini, and Cephalotaxus sinensis (A. Rheder and E.H. Wilson) H.L. Li; current convention is to treat C. sinensis at specific rank and reduce the others to varietal status or treat them as synonyms for C. harringtonia; regardless of one’s taxonomic persuasion, all of these plants serve similar purposes in the landscape. Cephalotaxus fortunei W.J. Hooker, the Chinese Plum Yew, is similar to C. harringtonii but posessing of longer leaves, a finer textured look, and a faster growth rate; Cephalotaxus fortunei is considerably less cold tolerant than C. harringtonii and is seldom seen in the trade, but is perhaps deserving of greater trialing in eastern portions of our region. References: Beale, 1960; Bloom, 2002; Dirr, 1998; Griffiths, 1994; Taylor, 1965; Tripp and Raulston, 1995. Copyrighted 2003 with all rights reserved by Michael A. Arnold; intended for future inclusion in Landscape Plants for Texas and Environs, Third Edition..
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