Bailby & Bailey: Woody Plants of National Parks 19 



Slender trees with spire-Iike tops; cones oblong-cylindric, 2'/2 ^o 4 inches 



long; in Northwest and Rocky Mountain parks 



Alpine fir {A. lasiocarpa). 



Cones spreading or hanging downwards; twigs rough after leaves fall (except 

 Douglas fir). 



Leaves prickly-pointed, the foliage often harsh PICEA. 



Young branchlets smooth. 



Cone-scales mostly angular and somewhat gnawed at the tips; western 

 species. 

 Leaves flattish in cross-section; occurs in coastal forests of the 



Northwest Sitka spruce (P. sitchensis) . 



Leaves 4-angled in cross-section; in Rocky Mountains and 



Southwest Blue spruce {P. pungens). 



Cone-scales mostly rounded, the margins not toothed; northern species 



found on Isle Royale White spruce (P. glauca). 



Young branchlets finely hairy. 



Cones oblong-cylindric, the scales rather soft and flexible though 



resilient; forest tree found in the western parks 



Engelmann spruce (P. Engelmanni). 



Cones ovoid, the scales stiff and rigid; northern species found on Isle 



Royale Black spruce (P. mariana). 



Leaves not prickly-pointed ; foliage soft. 



Leaves usually spreading all around the stems; cones with 3-pointed bracts 



piotruding from between the cone-scales; tip of tree erect 



Douglas fir (Pseudoisiiga laxifolia). 



Leaves spreading horizontally to form flat sprays, those on upper side 

 sometimes shorter; cones without protruding bracts; tip of tree 



whip- like, nodding TSUGA. 



Leaves flat; cones oval to oblong, ^4 to 1 inch long; lower elevations 



Western hemlock (7". heierophxilla) . 



Leaves rounded or ridged below; cones oblong-cylindric, I to 3 inches 



long; higher elevations Mountain hemlock (7". Meriensiana). 



2. Leaves needle-lilj;e, borne in bundles of 2 or more, or if single, then 

 nii(/i a stale-lilfe shealh ai the base. 



a. Needles on peg-like branchlets in cluslers of 15 to 40 ; deciduous 



trees lar;x. 



Cones oval to oblong, the scales numerous, shorter than the bracts; in Glacier 

 National Park. 



Branchlets smooth or becoming so; leaves triangular in crors-secticn ; trees of 



lower elevations Western larch (L. occidenialis). 



Branchlets woolly; leaves 4-angled in cross-seclicn ; trees of higher elevations 



Alpine larch (L. Lvalli). 



Cones somewhat globose, the scales few, longer than the bracts; leaves triangular in 



cross-section; on Isle Royale Eastern larch (L. laricina) . 



b. Needles in bundles of 1 to 5 ; evergreen trees PINUS. 



Needles I to 3 in a bundle. 



Needles 1 to 3 inches long, one or 2 in a bundle; cones egg-shaped to some- 

 what globose, ^4 to 2 inches long. 



Needle 1; seeds large; occus in Southwest and Sierra Nevada 



Singleleaf pifion (P. monoph\)lla) . 



