Picea retroflexa

Mast. (1906)

Common names

Green dragon spruce, 鳞皮云杉 lín pí yún shān, “scaly spruce” [Chinese].

Taxonomic notes

Type locality near Kangding, Sichuan (Masters 1906). Syn: P. gemmata Rehder & Wilson; P. asperata var. retroflexa (Mast.) Cheng; P. aurantiaca var. retroflexa (Mast.) C.T.Kuan & L.J.Zhou (Farjon 1998).

Picea retroflexa belongs to Clade III R of Ran et al. (2006), which contains P. abies and several other northeast Asian spruces that are united by a simple, obvious character: all have quadrangular needles, while other Asian spruces have laterally or dorsiventrally flattened needles. Subsequent genetic work has identified a "Picea asperata complex" recognizing close similarities with, probably, an early Neogene most recent common ancestor for P. asperata, P. aurantiaca, P. crassifolia, P. koraiensis, P. meyeri, P. neoveitchii, P. retroflexa and P. wilsonii. Speciation in this group has mainly been driven by regional tectonics, e.g. uplift of the Tibetan and Mongolian plateaus, and associated climate changes. In this group P. asperata, P. aurantiaca, and P. crassifolia are very close, sister species or even perhaps synonymous. These taxa are then sister to P. retroflexa (Liu et al. 2024). Some authors regard the relationship as so close as to reduce P. retroflexa to synonymy with P. asperata (Christian 2025). However, the analysis by Liu et al. (2024) only considered a single population of P. asperata, P. crassifolia, and P. retroflexa, and did not evaluate P. aurantiaca. Further molecular studies of the complex are needed to understand the extent of genetic variation and its biogeographic significance.

Description

Trees to 45 m tall and 150 cm dbh with a single straight, round trunk and a conical to columnar crown of numerous short, straight, horizontal primary branches. Bark rough and scaly, comprised of small, flaky plates. Twigs short, thick, light- or orange-brown, strongly ridged and grooved with conspicuous pulvini 1-2 × 1-1.5 mm. Foliage buds broad-conical, resinous, 5-10 × 5-10 mm, closely surrounded by curved leaves, with keeled, appressed, orange-brown bud scales that persist for several years at the base of the shoot. Leaves light- to glaucous-green, radially spreading, curved forward, 12-18 × 1.5-2 mm, linear, quadrangular with prominent ribs, apex sharply pointed, with stomata in paired bands of 2-3 lines on upper surfaces and 4-6 lines on lower surfaces. Pollen cones axillary, 3-5 cm long, ripening reddish yellow. Seed cones terminal, erect becoming pendulous, sessile, oval-oblong to cylindric-conical/obtuse, 8-13 × 2-4 cm when fully open; purple-red when immature, maturing purple-brown. Seed scales obovate, 15-20 × 12-15 mm at mid-cone, lower surface striated and shiny, outer margin slightly erose or denticulate, straight to reflexed when open. Bracts 5-6 mm long, included. Seeds ovoid-oblong, 3-4 mm long, dark brown, with a 10-15 × 5-7 mm pale brown obovate wing (Farjon 2010).

The relatively thick, ridged and grooved orange or orange-brown twigs; long pollen cones (over 15 mm); included but larger bracts (over 4 mm), and (in some cases) wide-opening, reflexed seed scales in open cones serve to distinguish P. retroflexa from P. asperata or P. aurantiaca.

Distribution and Ecology

China: W Sichuan, SE Xizang (Farjon and Page 1999). The primary areas of occurrence seem to be Kangding and Jiuzhaigou, both in Sichuan. Occurs in the subalpine zone at 3000-4000(-4700) m elevation, mostly on northern aspects with acid soils. Climate continental, relatively dry. Common associates at lower elevations include P. likiangensis var. rubescens, P. aurantiaca, Abies chensiensis, Tsuga chinensis, and Betula albo-sinensis; at higher elevations it commonly grows with Abies squamata (Farjon 2010).

Distribution of all species in the Picea asperata complex; data from GBIF (2026). P. retroflexa shown in light blue. Data have been edited to remove location duplicates, remove collections with coordinate uncertainty >10 km, and remove obvious extralimital occurrences. Specimens have not been checked and some may be misidentified. Click on any point for more info.

P. retroflexa was classified by the IUCN as "endangered" in 2010, largely due a limited distribution with evidence of historically recent population declines caused by intensive, unsustainable logging that largely ceased in 1990. Ongoing declines are suspected, though, due to fires and livestock grazing. There are also no research, monitoring, or related management programs to address the situation. The species does persist in at least one protected area, the Jiuzhaigou Valley Nature Reserve. The protected population is thought to contain less than 500 mature trees (Zhang et al. 2013). Also there are large uncertainties regarding the extent and status of the species; many published accounts of the forests of this region are unreliable regarding identification of Picea species, and their precise distributions must be inferred from a rather limited collection of herbarium specimens.

Potential impacts of climate change were assessed by applying species distribution models based on IPCC (2014) climate change scenarios and evaluating the outcomes under IUCN (2019) listing criteria. Results indicate a long-term reduction in area of occupancy of more than 50%, which maintains the species' current "Endangered" status (Dakhil et al. 2021).

Remarkable Specimens

No data as of 2026-10-22.

Ethnobotany

Specific uses of this species don't seem to have been documented, but it grows with other species of Picea and Abies that historically have been extensively exploited for their timber. As discussed above, this resulted in substantial population declines.

Observations

No data as of 2026-10-22.

Remarks

Masters (1906) states that pulvini on the shoots are bent back along the shoot axis (patenti-reflexi); this may be the origin of the epithet retroflexa. His description also states "very remarkable in its sharply decurved cone-scales", so the epithet may also allude to that character.

Citations

Christian, Tom. 2025. Trees and Shrubs Online: Picea asperata aggregate. https://www.treesandshrubsonline.org/articles/picea/picea-asperata-aggregate/, accessed 2026.10.14.

Dakhil, M. A., M. W. A. Halmy, Z. Liao, et al. 2021. Potential risks to endemic conifer montane forests under climate change: integrative approach for conservation prioritization in southwestern China. Landscape Ecology 36:3137-3151.

Farjon, Aljos and Christopher N. Page (compilers). 1999. Conifers. Status survey and conservation action plan. IUCN/SSC Conifer Specialist Group. IUCN, Gland, Switzerland and Cambridge, UK. 121p.

IPCC. 2014. The Physical Science Basis. Working Group I Contribution to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change—Summary for Policymakers. IPCC, Geneva.

IUCN. 2019. Guidelines for Using the IUCN Red List Categories and Criteria, Ver. 14. IUCN Standards and Petitions Subcommittee, IUCN, Gland, and Cambridge.

Liu, Yifu, Wenfa Xiao, Fude Wang, et al. 2024. Species divergence and environmental adaptation of Picea asperata complex at the whole genome level. Ecology and Evolution 14:e70126.

Masters, M. T. 1906. On the conifers of China. Journal of the Linnaean Society, Botany 37(262):410-424. Available: biodiversitylibrary.org/page/230356, accessed 2014.11.28.

Zhang, D., N. Li, T. Katsuki, and K. Rushforth. 2013. Picea retroflexa. The IUCN Red List of Threatened Species 2013: e.T34178A2849383. https://www.iucnredlist.org/species/34178/2849383. Accessed 2026.10.21.

See also

The species account at Threatened Conifers of the World.