Taxus fastigiata

18. Taxus fastigiata Lindley, Syn. Brit. Flora 241 (1829).  T. baccata (var.) fastigiata (Lindley) Loudon, Arb. frutic. britt. 4: 2066 (1838). T. baccata f. fastigiata (Lindley) Pilger, Planzenreich 18(iv, 5): 115. 1903. Taxus baccata var. hibernica Hook. ex Henkel & Hochstetter, Syn. Nadelhölzer 356 (1865), no specimens cited, none reported in the Lindley Herbarium. Type: Ireland, “mountains of Fermanagh” (transplanted to Florence Court in 1780, or 1760?), Willis, specimen unknown. Neotype (designated, Spjut 2007b)—from Florence Court—ex Herb. Jackson, Stewart, Sep. 1890 ( K!).

Taxus baccata (var.) columnaris Carrière, Traité gén. conif. 738. 1867, taxonomic synonym proposed. Taxus baccata f. columnaris (Carrière ) Beissner, Handb. Nandelholzk. 170. 1891.  Original material unknown, reported from horticulture in Versailles, France.  Distinguished by Carrière for its columnar habit with variegated color, and short branchlets on leader shoots.  Type undetermined.

Taxus baccata (var.) compressa Carrière, Traité gén. conif. 738. 1867, taxonomic synonym proposed. Taxus baccata (f.) compressa (Carrière ) Beissner, Handb. Nandelholzk. 171. 1891.  Compared by Carrière to his var. intermedia and to var. fastigiata.  Described by Ouden & Boom (1965) as dwarf, compact and conical in habit with numerous branchlets.  Type undetermined.

Taxus baccata stricta Lawson, Agric. Man. 398 1836 (n.v.), taxonomic synonym proposed. Taxus baccata f. stricta Rehder, Bibl. Trees 2. 1949.  Treated by Rehder as a synonym of the under the Irish yew.  Type unknown.

Irish yew. Distribution: British Isles (Ireland, England?).

18a. var. fastigiata. Tree, columnar and tapering to apex, or cylindrical in outline; branches and branchlets mostly ascending to erect; bud-scales loosely attached, 3–4 seriate on young growth, soon deciduous, chartaceous, pale brown to chocolate brown, occasionally basal scales deltoid smooth or with distinct midnerve on upper third, 1–3 mm long. Leaves lacking on lower parts of branchlets, crowded and overlapping near apex of branchlets, spreading in a radial manner, recurved, usually overlapping the branchlet near base of blade when pressed, broad linear, straight or slightly falcate, dark green, 1.5–3.0 cm long, 2.0–3.0 mm wide, 200–350 µm thick, slightly convex above to a low rounded midrib, plane to slightly concave below to a flush or low rounded midrib, plane to slightly revolute along margin, truncate (boat-shaped) in x-sect.; upper (adaxial) epidermal cells elliptical in transverse section, 8–15 µm tall, 10 µm wide, thin-walled; lower (abaxial) nonstomata epidermal cells similar in transverse section, 10–18 cells across the marginal zone, slightly larger on midrib, nearly quadrate to ± short rectangular, or trapezoidal, 1.5–4.5× l/w, narrowest in 4–11 rows near margins, slightly inflated, papillose on one-third to nearly halfway between margin and stomata band, or not at all papillose on marginal cells, epapillose on midrib, or obscurely papillose on outer rows of midrib cells; papillae positioned medially on midrib and marginal cells, submarginal on accessory cells, low and indistinct, ±concrescent in 1–2 alternate rows on each cell; stomata bands broader than the marginal region, with 8–10 (-11) rows of stomata, greenish. Cones not studied in detail.

     The Irish yew is thought to be native to mountains  in Fermanagh County (Cuilcagh Mountains) in northwestern Ireland where two female plants were reportedly discovered by a farmer, George Willis, in 1773, or earlier, who dug up the plants and planted one in his garden and gave the other to his landlord, who subsequently planted it at Florence Court (Veitch et al. 1881, with reference to The Gardeners Chronicle 1873: 1336 where further reference is made to undated manuscript by Lord Kinnaird); the one at Florence Court, which has been the source for "millions of yew plants distributed throughout the world" (Veitch et al. 1881), still survives (Internet sources, 2006), whereas Willis' plant died in 1865 (Veitch et al. 1881).   Additionally, Loudon (1838 with reference to MacKay, Flora Hibernica: 260) had suggested that Irish yew was in cultivation at Comber in the county of Down, and near the town of Antrim before 1780; an illustration of one such plant in Loudon (1838, shown below) was indicated to have been provided by MacKay, and which was accompanied by a description from the proprietor of the tree ( C. J. Andrews), and furthermore, Loudon (1838) implied that the original tree still existed in the mountains near Florence Court.  For many years it was thought that there were only female plants of the Irish yew (Loudon 1838), but male plants were later discovered at North Mundham in Sussex, England (Bean 1953; see also letter from Fletcher below accompanied by specimen collected in 1897).  One might wonder whether these male plants came from another source, but it is generally known that yew plants can occasionally reverse their sex, or can be monoecious to a limited extent as seen in the Dovaston yew. 

     The Irish yew (T. fastigiata) has long been considered distinct from other yews for its erect habit and dark green leaves in whorl-like arrangement; yet, most authorities treat it as a synonym of T. baccata.  This is because plants reportedly grown from seed of Irish yew, which are thought to have been pollinated by "common yew," are often regarded as the same as the "common yew" (Veitch et al. 1881)   However, the Irish yew is viewed by this author as having ancestral features worthy of  species status even though it may form hybrids.  In many specimens of the Irish yew, leaves appear distinct for their boat-like shape in cross section, especially the sharply angled margins; no other species of yew show this. Additionally, the abaxial epidermal cells often lack papillae across a relatively broad marginal region, and often entirely across the midrib as well, a feature that is generally seen in the Cuspidata Alliance. 

     The radial orientation of leaves that characterizes the Irish yew is also much like the E Asian T. umbraculifera.  They differ in the manner in which leaves spread from branches.  In the Irish yew, the leaves spread by curving of the blade downwards from base towards apex, whereas in the umbrella yew, the leaves bend more abruptly in that they are sharply (reflexed) near the petiole.  Other species, which have radial orientation of leaves—the  E Asian species, T. caespitosa and the European T. baccata var. ericoides (Morocco)—differ in the leaves curving upwards instead of downwards.

     However, some specimens in the T. cuspidata Alliance—from the islands of Sakhalin, Hokkaido, and Honshu—have been difficult to distinguish from the Irish yew. For example, I annotated a specimen collected by  Dvorakovskia & Bokina  (A) from Sakhalin Island as T. fastigiata in June 1996, because of leaves noticeably recurved and dark green in color similar to that of the Irish yew.  Branching, leaf arrangement and leaf anatomy of this specimen also compared favorably with T. baccata var. glauca, especially in view of another specimen from Sakhalin Island, Flanakan & Kirkham 203 (K), that appeared more similar to T. baccata var. glauca.  Specimens such as these appear infrequent, and while they have been difficult to resolve taxonomically, they have been recently interpreted as belonging to T. caespitosa var. latifolia, which is common on the islands of Hokkaido and Honshu.

     Radial arranged leaves, which are generally associated with plants having an erect habit, are rare in Taxus.   In the Euro-Mediterranean, most specimens with these features occur near the western distribution limits of the genus. Taxus fastigiata, for instance, is known primarily from two plants found in northwestern Ireland.  Near the southwestern range of the genus is Taxus baccata var. ericoides, known only from middle Atlas of Morocco (near Ifrane, 1700 m).  Other varieties of Taxus baccata, which also have limited geographical occurrences, exhibit a south to north clinal relationship in phyllotaxy with the leaf arrangement varying from radial to distichous.  Radial types include Taxus baccata var. erecta found only in Spain and  Portugal and Taxus baccata var. pyramidalis occurring sporadically in  Algeria, Spain, France, and Norway. The more common leaf arrangement—spreading horizontally in one plane so as to appear in two-ranks—as exemplified by T. baccata var. baccata and T. baccata var. washingtonii—may have evolved, however, by introgression with ancestors related to T. biternata and Taxus canadensis. 

     Introgression between Taxus fastigiata  and T. recurvata is also evident with variation appearing to correspond to a latitudinal cline instead of a south-north longitudinal cline mentioned above.  Plants of T. recurvata with more leafy branches, and with leaves also showing more radial orientation, occur in the British Isles (e.g. cv., 'Expansa'), in contrast to less leafy plants found mostly in central and eastern Europe to southwest Asia (e.g., T. recurvata var. linearis).  Taxus fastigiata var. sparsifolia, an endemic to the British Isles, may also prove to be a hybrid between T. fastigiata and T. recurvata; however, the introgression and the geographical cline that is evident, may be a product of former contact with ancestral Taxus contorta instead of T. recurvata.   Many specimens of Taxus recurvata from the Euro-Mediterranean were found to have reddish parenchyma cells in the spongy mesophyll, a feature that is more pronounced and characteristic of Taxus contorta. Thus, while one may speculate that Taxus contorta may have retreated into Europe since the Pliocene, it may also have found refuge in the northwest Himalayas as a result of the Himalayan uplift.  Molecular studies, thus, may help determine to what extent Taxus fastigiata, T. canadensis and T. contorta have contributed to the taxonomic complexity of yew in the Euro-Mediterranean.

     The specimens shown below undoubtedly include hybrids for which I do not make any further distinction; however, the Hick's yew, which has a similar habit, and which may be a hybrid involving T. fastigiata, is treated as a distinct variety of Taxus umbraculifera based specimens that appear to have been collected in the wild of Japan and are indistinguishable from its type.

Representative Specimens—Ireland: Florence Court, Stewart, Sep. 1890 (K); ex Herb. Lange (K). Cultivation—Europe—England: Fletcher, 13 Mar. 1897 (K); Yorkshire with specimen ex Herb. Baker, Oct. 1837 (BM). Portugal: Rainba 1873 (S: C-2069). Switzerland: f. aurea, C. Baenitz s.n (US: 139642). Pinetum Boissier, Genf, 1953, ex Herb. Dendrol. Schneider, Jeps. s.n. (A). Granvik, Sep. 1886 (BM). Ex Herb. Zuccarini, annotated T. hybernica (M). Boorman s.n. (A). North America—U.S.A.: Oregon: near Salem, O Brien C, D, F, G  (wba)