''Picea martinezii'', the Martinez spruce, is a medium-sized

evergreen In botany, an evergreen is a plant which has Leaf, foliage that remains green and functional throughout the year. This contrasts with deciduous plants, which lose their foliage completely during the winter or dry season. Consisting of many diffe ...

tree In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, e.g., including only woody plants with secondary growth, only ...

growing to 25–35 m tall, and with a trunk diameter of up to 1 m. It is native to northeast

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

, where it occurs at six localities in the

Sierra Madre Oriental The Sierra Madre Oriental () is a mountain range in northeastern Mexico. The Sierra Madre Oriental is part of the American Cordillera, a chain of mountain ranges (cordillera) that consists of an almost continuous sequence of mountain ranges that ...

mountains in

Nuevo León Nuevo León, officially the Free and Sovereign State of Nuevo León, is a Administrative divisions of Mexico, state in northeastern Mexico. The state borders the Mexican states of Tamaulipas, Coahuila, Zacatecas, and San Luis Potosí, San Luis ...

. It grows at moderate altitudes from 2150–2600 m, growing along streamsides in mountain valleys, where moisture levels in the soil are greater than the otherwise low rainfall in the area would suggest. The

bark Bark may refer to: Common meanings * Bark (botany), an outer layer of a woody plant such as a tree or stick * Bark (sound), a vocalization of some animals (which is commonly the dog) Arts and entertainment * ''Bark'' (Jefferson Airplane album), ...

is thin and scaly, flaking off in small circular plates 5–10 cm across. The crown is conic, with widely spaced branches with drooping branchlets. The shoots are stout, pale buff-brown, glabrous, and with prominent pulvini. The

leaves A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, ...

are needle-like, 23–35 mm long, stout, moderately flattened in cross-section, bright glossy green with inconspicuous lines of

stomata In botany, a stoma (: stomata, from Greek ''στόμα'', "mouth"), also called a stomate (: stomates), is a pore found in the epidermis of leaves, stems, and other organs, that controls the rate of gas exchange between the internal air spa ...

; the tip is viciously sharp. The

cones In geometry, a cone is a three-dimensional figure that tapers smoothly from a flat base (typically a circle) to a point not contained in the base, called the ''apex'' or '' vertex''. A cone is formed by a set of line segments, half-lines, ...

are pendulous, broad cylindrical, 8–16 cm long and 3 cm broad when closed, opening to 6 cm broad. They have stiff, smoothly rounded scales 2-2.5 cm broad, and are green, maturing pale brown 6–8 months after pollination. The

seed In botany, a seed is a plant structure containing an embryo and stored nutrients in a protective coat called a ''testa''. More generally, the term "seed" means anything that can be Sowing, sown, which may include seed and husk or tuber. Seeds ...

s are black, 4 mm long, with a 12–16 mm long pale brown wing. Martinez spruce was only discovered in 1981, and is

critically endangered An IUCN Red List critically endangered (CR or sometimes CE) species is one that has been categorized by the International Union for Conservation of Nature as facing an extremely high risk of extinction in the wild. As of December 2023, of t ...

with just six small populations, comprising about 1,000 trees. Fossil evidence shows it had a wider distribution in the past, south to central Mexico. It is related to Chihuahua spruce from northwest Mexico, but differs in the longer, green leaves, and the larger, broader cones with larger scales. No other related spruces are found in

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

, with its next-closest relatives in eastern

Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...

. It is a very attractive tree and is starting to be planted as an ornamental tree in botanical gardens, particularly valued in warm areas as it is one of the most heat-tolerant of all spruces. It is named after the Mexican

botanist Botany, also called plant science, is the branch of natural science and biology studying plants, especially Plant anatomy, their anatomy, Plant taxonomy, taxonomy, and Plant ecology, ecology. A botanist or plant scientist is a scientist who s ...

Maximino Martínez.

References

External links

Gymnosperm DatabasePhoto of tree
{{Taxonbar, from=Q3731407 martinezii Trees of Northern America Critically endangered plants Flora of the Sierra Madre Oriental