Pinus leiophylla aka Chihuahuan Pine

Pinus leiophylla, or smooth-leaf pine, is in the pine family. Its home range starts in southeastern Arizona and southwestern New Mexico. It runs through Mexico, south to Oaxaca. This pine keeps its leaves year-round. It grows in mountain woods with pines, or pines and oaks. Trees often grow apart, mixed with other pines. Its wide range helps explain its Least Concern status. This status rates its risk in the wild. Logging has still harmed woods in parts of Mexico.

Size reports differ, so leave space for a large tree. Virginia Tech gives about 50 feet [15 metres]. Useful Tropical Plants lists 66 feet [20 metres]. Some accounts reach 115 feet [35 metres]. These sources give no clear size range for gardens. The crown is open, with raised branches. Its top is round or flat. Much of the straight trunk can lack branches. The thick bark is rough and almost black. It has ridges and deep cracks that run upright. Lighter parts have reddish brown tones.

The thick needles look blue-green. They have white bands of stomata, or leaf pores. Virginia Tech says they grow in groups of three. Each needle is about 2.5–4.5 inches long. Each group's sheath falls off in its first year. Reddish brown twigs bear slim buds with sharp tips. Both male and female cones grow on one tree. Male cones change from purple to yellow in spring. Red female cones grow at branch tips. Wind moves the pollen. Ripe, woody cones turn reddish brown to grey-brown. They have long stalks and small prickles on their scales. Cones take three years to ripen. They stay on the tree for years.

Useful Tropical Plants gives a medium rate of growth. Its account of cold tolerance allows brief spells near freezing only. The evidence gives no firm hardiness zone. Nor does it state this species' water needs. New trees can grow from seed. Six weeks of cold treatment may help stored seed sprout. The source says to plant young trees before they grow large. Older trees may stall when moved, since they have few roots.

People harvest this pine for wood and resin. They plant it for wood beyond its home range, including Africa. Its resin yields turpentine. Its needles yield tan or green dye. Work to process pulpwood can also yield vanillin flavouring. The source notes use as medicine, but does not show treatment safety. It gives no firm account of how this species' seeds taste. The evidence names no pests or diseases specific to this species.