ENCICLOPEDIA DE LAS CONÍFERAS

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Picea alcoquiana (Veitch ex Lindl.) Carrière (syn. P. bicolor Maxim.) – Alcock’s Spruce

A tall tree to 35m in height found in mixed coniferous forests at 700–2,180m in the mountains of Japan: central Honshu. The climate is cool and wet with snowy winters: the soils are of volcanic origin. The crown is pyramidal or conical with horizontal branches; branchlets pale orange-brown with ovoid-conical, 3–5mm long, brown. The needles are spirally arranged, curving forward on upper side of the branchlets, parted, 8–20(–25)mm long and 1–1.5mm wide, quadrangular in cross-section, dark green above, blue-green beneath, with white stomatal bands on all faces, giving the ‘bicolour’ effect. The pollen-cones are 1–1.5cm long, rose-red, later yellow. The seed-cones are cylindric to ovoid, (4–)6–12(–15) x (2.5–)3–5(–5.5)cm (with opened scales), purple-violet ripening to reddish brown. The seed-scales are obovate-rhombic, notched at the apex or entire, often reflexed. Hardiness zone 6.

This species was discovered by J.G. Veitch c.1860 and named after Sir Rutherford Alcock, who was Queen Victoria’s minister at the Court of Jeddo (Tokyo). Treated as Picea bicolor by some authorities in the past.

Var. alcoquiana – central Honshu. The new shoots are glabrous and the needles are 8–15mm long, slightly curved forwards. The seed-cones are 6–10cm long, scales undulate and notched at apex.

Var. acicularis (Maxim. ex Beissn.) Fitschen (syn. P. shirasawae Hayashi) – central Honshu (Yatsuga-take Mountains). The new shoots are pubescent and the needles are 13–25mm long, strongly curved, glaucous. The seed-cones are 6–15cm long, scales with an entire or denticulate margin. A clones or clones selected for their more densely arranged, blue-white needles are available in the trade.

Var. reflexa (Shiras.) Fitschen – central Honshu (Akaishi Range). The new shoots are pubescent and the needles are 8–13mm long, curved forwards. The seed-cones are 4–7.5cm long, scales with an entire margin, apically narrowed and reflexed.

‘Acicularis’ A clone from var. acicularis which, under ICNCP Art. 21.5 (2009), retains that name when brought into cultivation as a cultivar.

‘Dwarf Tigertail’ Syn. of ‘Howell’s Dwarf’.

‘Howell’s Dwarf’ syn. ‘Tigertail’; ‘Dwarf Tigertail’) A spreading, flat-topped, slow-growing bush with ascending branches. Needles green with silver-blue undersides and a hint of yellow on the most exposed surfaces. In ten years 1 x 1.5m. Received by John Vermeulen & Son, Inc., NJ, USA, from Skylands, NJ, USA, as ‘Howell’s Tigertail’ and introduced in 1972. Renamed to avoid confusion with the common name (tiger tail) of P. torano. (W, I)

‘Prostrata’ A dense, low, spreading, almost prostrate cultivar with small blue-green needles. In ten years 30 x 70cm. Distributed before 1979 by Průhonice Park, Czech Republic. This name in Latin form is only acceptable if proved to have been published before 1959. (W, BC)

‘Tigertail’ Syn. of ‘Howell’s Dwarf’.

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Picea asperata Mast. – dragon spruce

A tall tree growing to 30–45m tall. It is native to the high mountains of C China. It is found at an elevation of 1,500–3,800m on mountain podzols in a subalpine continental climate with cold winters and dry summers. The crown is narrowly conical, tapering towards the top with horizontally spreading branches. The branchlets are yellowish brown or orange turning grey and the buds ovoid-conical, 6–12mm long, yellowish brown. The needles are bluish green and radially arranged, 10–20mm long and 1–1.8mm wide, quadrangular in cross-section with 3–4 lines of stomata on each face. The pollen-cones are 1–1.5cm long, reddish, turning yellow. The seed-cones are cylindric, (5–)6–15 x (2.5–)3–4.5cm (with opened scales), purplish green at first, ripening to brown. Hardiness zone 6.

Var. asperata – Gansu, Ningxia (Helan Shan), east Qinghai, southwest Shaanxi and Sichuan. The new shoots are glabrous or pubescent, bud-scales mostly adpressed. The seed-cones are (5–)6–12 x (2.5–)3–4cm (with opened scales); seed-scales obovate-oblong with upper margin obtuse, rounded or truncate.

Var. notabilis Rehder & E.H. Wilson – west Sichuan. The new shoots are glabrous, bright orange-brown, bud-scales loosely imbricate, apically reflexed and yellowish brown. The seed-scales are rhombic-oblong, apex notched.

Var. ponderosa Rehder & E.H. Wilson – west Sichuan. The seed-cones are 12–15 x 4–4.5cm; seed-scales coriaceous, rigid, with slightly elongated, curved and usually notched apex.

‘China Blue’ A medium-sized, upright, broadly pyramidal plant with grey-blue needles. In ten years 2.5 x 1m. Originated in 1985 by Buchholz & Buchholz Nursery, OR, USA.

‘Arturs Dominiks’ A compact slow-growing bush without a central leader. The radially arranged foliage is bluish green with wine-red new growth-tips in spring. In ten years 1.5 x 0.8m. Originated in 1999 as a seedling by Aris Auders, Latvia.

‘Bedgebury WB’ A compact dwarf with short twisted bluish green foliage. In ten years 30 x 30cm. Originated in Bedgebury National Pinetum, UK. The cultivar name has also been used under P. omorika: only one such use can be accepted, to be decided by the International Cultivar Registration Authority.

‘Glauca’ A tree of normal habit but foliage glaucous blue. Raised before 1936 by Herm. A. Hesse, Germany. (B, W, G)

‘Hunnewelliana’ A mound-shaped dwarf with grey-green foliage. Raised in a Hunnewell arboretum in Wellesly, MA, USA from seed brought back from China by E.H. Wilson. Plants were distributed before 1923. The cultivar name has also been used under P. pungens: only one such use can be accepted, to be decided by the International Cultivar Registration Authority. (H, W)

‘Kórnik’ A slow-growing fastigiate plant with bluish green foliage. Annual growth 5–7cm. Originated before 2005 in Kórnik Arboretum, Poland.

‘Mongolei’ A very compact, globose dwarf with short blue-green needles. Annual growth 1–2cm. Originated as a witches’ broom. Cultivated in Germany before 2000.

‘Morton Arb’ A slow-growing, compact, upright plant with bluish green foliage. In ten years 1.5 x 1m. Originated in Morton Arboretum, IL, USA before 2000.

‘Nigrans’ A slow-growing, upright cultivar with rich dark green needles. Originated in the USA before 2005; listed by Arrowhead Alpines Nursery, MI, USA.

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Picea aurantiaca Mast.– orange spruce

A tall tree growing to 20–25m in height. It occurs in China: west Sichuan, in mountains at altitudes between 2,600 and 4,000m. The climate is cold and the soils mostly calcareous. The crown is narrowly conical with short spreading branches and thick, rigid, characteristic orange branchlets. The buds are broadly ovoid-conical, 4–6mm long, hidden by the needles. The needles are spirally arranged and directed forwards, blue-green or grey-green, 8–18mm long and 1.2–2.3mm wide, quadrangular in cross-section with stomata in 4 bands of 3–6 lines. The pollen-cones are 1.5–2cm long, reddish, then yellow. The seed-cones are cylindric, 10–12 x 4–4.5cm (with opened scales), bright red, maturing to glossy reddish brown. The seed-scales are rhombic-ovoid with the apex nearly rounded. Hardiness zone 5.

Closely related to P. retroflexa and P. asperata. It is treated as a variety of P. asperata in Wu Zheng-Yi & Raven, P.H. (eds), Flora of China Vol. 4 (1999).