Picea breweriana Seeds | Brewer’s Spruce
LATIN NAME: Picea breweriana
COMMON NAME: Brewer’s Spruce
Plant Profile
Brewer spruce is the spruce that hangs, and once seen it is not confused with another. The branchlets droop from the main limbs in long, slender, curtain-like sprays, forty to eighty centimetres of them, and on a mature tree the effect is of a conifer draped in green ropes. The needles are flattened, blunt, dark green above with two white bands beneath, and they are arranged all round the shoot rather than swept to one side. Cones are cylindrical, ten to fifteen centimetres, violet when young and brown at maturity, with ragged scales. In the wild it is a tree of ten to twenty metres in cultivation and up to forty in favoured sites, with a narrow, spire-like crown. It is restricted to the Klamath-Siskiyou mountains of southwestern Oregon and northwestern California, on serpentine and other poor soils, and it is nowhere common.
Science & Biotechnology
Picea breweriana is one of the palaeoendemics of the Klamath-Siskiyou region, a flora that survived the Pleistocene in isolated refugia and now contains a high proportion of local endemics. Its nearest relatives are in Asia rather than in North America, which is one line of evidence for its antiquity, and its weeping branchlets are unique in the genus. The species is slow and long-lived, and it regenerates poorly: seed production is irregular, the cones are often damaged by insects, and the seedlings need moist but well-drained ground and some shade, conditions that are scarce on the dry, exposed ridges where the adults grow. It is also susceptible to spruce beetle and to root rot in warm, wet soils. Populations are small and fragmented, and the species is assessed as near threatened, with fire and climate change the main long-term risks.
Uses & Benefits
Its use is ornamental: a specimen tree for a large garden or arboretum, planted for the weeping habit and the late, dark foliage. It is slow enough that it never overwhelms a site, and it is one of the few conifers that looks better at thirty years than at five. The timber is of no commercial importance given the small volumes and the protected status of most stands. In the wild the tree matters for stabilising steep, unstable slopes and for the deep shade it casts over streams, which keeps water temperatures down for salmonids. There is no medicinal record of consequence. Its scarcity in cultivation makes it a collector’s plant, and good seed is worth taking when it is offered, since cone crops in the wild are irregular.
Growing from Seed
Sow in late winter after eight to twelve weeks of cold, moist stratification at 4 degrees; germination is slow and often staggered over six weeks at 15 to 18 degrees. Use a humus-rich, acid, well-drained mix, and give the seedlings light shade in their first summer, since they burn in full sun when young. Keep them moist but never waterlogged, and pot on every second year, because the roots are slow to colonise a new pot. Plant out at thirty to forty centimetres in autumn, in deep, cool, moist but drained soil, in sun or partial shade with shelter from drying wind. Mulch and keep the ground clear for the first three years. Expect fifteen to twenty-five centimetres a year at best, and do not expect cones before the tree is thirty.
Our Take
A rare, slow, weeping spruce for a large garden or collection, worth growing for the branchlets alone. Give it cool acid soil, shelter and decades.
Related Reading
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