5a. Picea engelmannii Engelmann var. engelmannii
Picea glauca (Moench) Voss subsp. engelmannii (Engelmann) T.M.C. Taylor; P. columbiana Lemmon; P. engelmannii var. glabra Goodman
Trees to 60m; trunk to 2m diam.; crown narrowly conic. Bark gray to reddish brown. Branches spreading horizontally to somewhat drooping; twigs not pendent, rather stout, yellow-brown, finely pubescent, occasionally glabrous. Buds orange-brown, 3--6mm, apex rounded. Leaves 1.6--3(--3.5)cm, 4-angled in cross section, rigid, blue-green, bearing stomates on all surfaces, apex sharp-pointed. Seed cones 3--7(--8)cm; scales diamond-shaped to elliptic, widest above middle, 13--20 ´ 9--16mm, flexuous, margin at apex irregularly toothed to erose, apex extending 3--8mm beyond seed-wing impression. 2 n =24.
Montane and subalpine forests; 1000--3000m; Alta., B.C.; Ariz., Calif., Colo., Idaho, Mont., Nev., N.Mex., Oreg., Utah, Wash., Wyo.; Mexico.
Only Picea engelmannii var. engelmannii occurs in the flora. In Mexico the species is also represented by P . engelmannii var. mexicana (Martínez) R. J. Taylor & T. F. Patterson.
Although Picea engelmannii varies considerably over its broad distributional range, the variation is continuous, militating against recognition of multiple varieties (R.J. Taylor and T.F. Patterson 1980). In the northern part of its range, it hybridizes freely and completely intergrades with P . glauca , as noted above.
LaRoi, G.H. and J.R. Dugle. 1968. A systematic and genecological study of Picea glauca and P. engelmannii, using paper chromatography of needle extracts. Canad. J. Bot. 46: 649--687.