Juniperus brevifolia

(Seub.) Antoine 1857

Common names

Azores juniper; cedro [Portuguese].

Taxonomic notes

Originally described in 1844 by Moritz August Seubert in Flora Azorica, Volume 26 as J. oxycedrus var. brevifolia Seub. In 1857, Franz Antoine elevated it to species rank.

Juniperus sect. Juniperus. Terpene and molecular analyses place J. brevifolia sister to J. navicularis, which occurs in coastal Portugal. J. deltoides of interior Europe is also in this clade (Adams 2014). All three species were originally treated within J. oxycedrus, but molecular data have shown otherwise, as well as helping to elucidate morphological and ecological differences; see J. deltoides for further discussion.

Description

Dioecious evergreen shrubs or small trees with a broad pyramidal crown of erect branches. Bark purplish brown, exfoliating in strips. Leaves needle-like, 3-10 × 1-2 mm, strongly curved, the adaxial face with two broad, white stomatal bands. Pollen shed in spring. Seed cones ripening in 2nd year, subglobose, 7-9 mm diameter, green and pruinose maturing to dark coppery brown; 3 ovoid seeds per cone (Adams 2014).

Distribution and Ecology

Portugal: Azores; Corvo, Faial, Flores, Pico, Santa Maria, Sao Jorge, Sao Miguel, and Terceira islands; it is most abundant on Pico and Terceira islands. Found on mountain slopes at (250-)250-800(-1500) m elevation on volcanic rock (Adams 2014); the climate is almost perennially damp due to the prevailing westerly winds. It is a constituent of the Macaronesian evergreen forest, a formerly extensive vegetation type that has been greatly reduced and fragmented since humans colonized the islands (Farjon 2010).

The IUCN conservation assessment has varied between "Endangered" and "Vulnerable" assessments. Currently it is "Vulnerable" due to the relatively large area of occupancy, over 500 km². However the extant populations are severely fragmented and in steep decline; large mature trees are now rare and most extant populations are comprised of young, shrubby trees. The primary threats to the species include land conversion for agroforestry and livestock ranching; timber harvest; competition from invasive weeds; and climate change. However, approximately 75% of the extant populations are now protected in various nature reserves, and plans are in place to preserve habitat, control invasive species, reduce habitat fragmentation, and otherwise contribute to species conservation (Thomas 2011).

Zone 9 (cold hardiness limit between -6.6°C and -1.1°C) (Bannister and Neuner 2001).

Remarkable Specimens

No data as of 2023.03.03.

Ethnobotany

No reported uses (Adams 2014) and rare in cultivation, excepting major botanical gardens (Farjon 2010).

Observations

See the collection records on iNaturalist.

Remarks

The epithet means "short-leaved."

Citations

Adams, Robert P. 2014. Junipers of the World: The Genus Juniperus, fourth edition. Bloomington, IN: Trafford Publishing. 415 pp.

Antoine, Franz. 1857. Die Cupressineen-Gattungen Arceuthos Juniperus und Sabina. Wein: Beck. p. 16, tt. 20-22.

Thomas, P. 2011. Juniperus brevifolia (errata version published in 2018). The IUCN Red List of Threatened Species. https://www.iucnredlist.org/species/30326/136559787, accessed 2022.12.21.

See also

Elwes and Henry 1906-1913 at the Biodiversity Heritage Library. This series of volumes, privately printed, provides some of the most engaging descriptions of conifers ever published. Although they only treat species cultivated in the U.K. and Ireland, and the taxonomy is a bit dated, still these accounts are thorough, treating such topics as species description, range, varieties, exceptionally old or tall specimens, remarkable trees, and cultivation. Despite being over a century old, they are generally accurate, and are illustrated with some remarkable photographs and lithographs.

Farjon (2005) provides a detailed account, with illustrations.

Mairal, Mario, Juli Caujapé-Castells, Loïc Pellissier, Ruth Jaén-Molina, Nadir Álvarez, Myriam Heuertz, and Isabel Sanmartín. 2018. A tale of two forests: ongoing aridification drives population decline and genetic diversity loss at continental scale in Afro-Macaronesian evergreen-forest archipelago endemics. Annals of Botany 122(6):1005–1017, https://doi.org/10.1093/aob/mcy107

Threatened Conifers of the World.