[4][5] Brewer spruce is a large evergreen conifer growing to 20–40 metres (66–131 ft) tall, exceptionally 54 m, and with a trunk diameter of up to 1.5 m. The bark is thin and scaly, and purple-gray in color.

The leaves are borne singly on the pulvini, and are needle-like (though not sharp),[6] 15–35 mm long, flattened in cross-section, glossy dark green above, and with two bands of white stomata below.

It is also susceptible to wildfire due to its thin bark and pendulous foliage, and therefore is seen to occur in exposed sites with poor, rocky soils, often at high elevation, where competition with other fire-sustaining conifers is reduced.

[12] It is endemic to the Klamath Mountains of southwest Oregon and northwest California, and grows at moderately high altitudes, from 1,000–2,700 m (3,300–8,900 ft) above sea level.

[7][8][1][14][15] Outside its native range, P. breweriana is a highly-valued ornamental tree in gardens, particularly in Great Britain and Scandinavia, where it is appreciated for its dramatically pendulous foliage.