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blue spruce, Colorado blue spruce, pino real, épinette bleue

black hills spruce, Porsild spruce, western white spruce, white spruce, épinette blanche

Habit Trees to 50m; trunk to 1.5m diam.; crown broadly conic. Trees to 30m; trunk to 1m diam.; crown broadly conic to spirelike.
Bark

gray-brown.

gray-brown.

Branches

slightly to strongly drooping;

twigs not pendent, stout, yellow-brown, usually glabrous.

slightly drooping;

twigs not pendent, rather slender, pinkish brown, glabrous.

Buds

dark orange-brown, 6–12mm, apex rounded to acute.

orange-brown, 3–6mm, apex rounded.

Leaves

1.6–3cm, 4-angled in cross section, rigid, blue-green, bearing stomates on all surfaces, apex spine-tipped.

(0.8–)1.5–2(–2.5)cm, 4-angled in cross section, rigid, blue-green, bearing stomates on all surfaces, apex sharp-pointed.

Seed

cones (5–)6–11(–12)cm;

scales elliptic to diamond-shaped, widest below middle, 15–22 × 10–15mm, rather stiff, margin at apex erose, apex extending 8–10mm beyond seed-wing impression.

cones 2.5–6(–8)cm;

scales fan-shaped, broadest near rounded apex, 10–16 × 9–13mm, flexuous, margin at apex ± entire, apex extending 0.5–3mm beyond seed-wing impression.

2n

=24.

=24.

Picea pungens

Picea glauca

Habitat Midmontane forests Muskegs, bogs, and river banks to montane slopes
Elevation 1800–3000m (5900–9800ft) 0–1000m (0–3300ft)
Distribution
from FNA
AZ; CO; ID; NM; UT; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
AK; ME; MI; MN; MT; NH; NY; SD; VT; WI; WY; AB; BC; MB; NB; NF; NS; NT; ON; PE; QC; SK; YT; SPM
[WildflowerSearch map]
[BONAP county map]
Discussion

Limited hybridization occurs between Picea pungens and P. engelmannii (R.Daubenmire 1972; R.J. Taylor et al. 1975).

Blue spruce (Picea pungens) is the state tree of Colorado (as Colorado blue spruce) and Utah.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

In areas of sympatry Picea glauca and P. engelmannii regularly hybridize and intergrade completely (R.Daubenmire 1974; E.H. Garman 1957; K.W. Horton 1959; L.Roche 1969; T.M.C. Taylor 1959). This has greatly complicated the taxonomy of P. glauca, a dominant tree of interior forests of Canada and Alaska. Three varieties have been recognized. Picea glauca var. albertiana was described as having unusually prominent leaf bases, cones nearly as broad as long, cone scales acute and broader than long, and an unusually narrow crown. These are common characteristics of hybrids (e.g., R.Daubenmire 1974). Picea glauca var. porsildii was described as differing from the type variety by having smooth bark with resin blisters, short angular cone scales, an unusually broad crown, and pubescent twigs. These characteristics, also largely intermediate between those of P. glauca var. glauca and P. engelmannii, may reflect hybridization where the species overlap. Although the two varieties noted above are reported from well beyond the range of sympatry, the diagnostic characteristics are not well correlated and occur rather sporadically. Also the most distinctive feature of the varieties, the crown shape, is in part responsive to competitive pressures. Because of the problems of hybridization and sporadic occurrence of key characters, P. glauca is treated here in the broad sense.

Picea glauca (white spruce) is the provincial tree of Manitoba and the state tree (as Black Hills spruce) of South Dakota.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 2. FNA vol. 2.
Parent taxa Pinaceae > Picea Pinaceae > Picea
Sibling taxa
P. abies, P. breweriana, P. engelmannii, P. glauca, P. mariana, P. rubens, P. sitchensis
P. abies, P. breweriana, P. engelmannii, P. mariana, P. pungens, P. rubens, P. sitchensis
Synonyms P. parryana Pinus glauca, Abies canadensis, P. alba, P. alba var. albertiana, P. albertiana, P. canadensis, P. canadensis var. glauca, P. glauca var. albertiana, P. glauca var. densata, P. glauca var. porsildii, Pinus alba
Name authority Engelmann: Gard. Chron. n. s. 11: 334. (1879) (Moench) Voss: Mitt. Deutsch. Dendrol. Ges. 16: 93. (1907)
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