Picea glauca
 
White Spruce

Twig

Duck Mountain Provincial Park
15-May-2015

Note the leaves are borne singly and are spirally arranged.

The key answers below are taken from Conifers & Catkin-Bearing Trees and Shrubs of Saskatchewan by George Argus, Vernon Harms, Anna Leighton, and Mary Vetter.  This book is published jointly by Flora of Saskatchewan Association and Nature Saskatchewan.

bullet

Glauca: Answers to key questions leading to this species. 
bullet

Seed cones ovoid-oblong, deciduous, falling the first winter, 2.5-6 (7) cm long; seed cone scales 10-16 mm long, margin near apex +/- entire; needles (0.8) 1.5-2 (2.5) cm long, mostly sharp-pointed, glaucous, green or blue-green; twigs and bud scales glabrous.  NOT [Seed cones ovoid-subglobose, persisting on tree for several years, 1.5-2.5 (3.5) cm long; seed cone scales 8-12 mm long, margin at apex irregularly toothed; needles 0.6-1.5 (2) cm long, mostly blunt-tipped, glaucous, blue- to grey-green; twigs and bud scales puberulent.]

 

bullet

Picea: Answers to key questions leading to this genus. 
bullet

Needles borne singly along branches, not in fascicles scaly-sheathed at base or on short shoots.  NOT [Needles on year-old and older branches borne either in groups (fascicles) of 2 with each fascicle scaly-sheathed at base at least when young, or in clusters of 12-25 on short shoots with clusters not scaly sheathed.]

bullet

Needles 4-angled in cross-section, either sharp-pointed or blunt-tipped, rigid; seed cones falling as a unit, not disintegrating by shedding scales individually from cone axis; twigs conspicuously roughened by decurrent, spreading or appressed, peg-like projections (pulvini) persisting after needles fall.  NOT [Needles flattened, frequently grooved adaxially, usually rounded or notched at apex, flexible; seed-cones not falling whole but scale by scale, leaving naked cone axes persisting as erect "spikes" on branches; twigs not roughened by decurrent, projecting, peg-like leaf-bases.]

 

bullet

Pinaceae: Answers to key questions leading to this family. 
bullet

Leaves needle-like, alternate or fascicled/clustered, shed individually from branchlets (usually shed as fascicles in Pinus); seed cone scales imbricate; seed cones dry; seeds adaxial and 2 per scale.  NOT [Leaves needle-like or scale-like, alternate, opposite or whorled, persistent on shoots, shedding with branchlets with age; seed cone scales fused or imbricate; seed cones berry-like (Juniperus) or dry (Thuja); seeds adaxial or terminal and 1-20 per scale.]