One of the dominant trees in the Rocky Mountain region, along with the Subalpine Fir, Abies lasiocarpa, Engelmann Spruce are medium-sized conifers that grow best in cold, harsh conditions at high altitudes. They have short needles and cones and typically grow in a narrow vertical fashion.
Picea engelmanii (Engelmann Spruce, Mountain Spruce)
Hardiness Zones: 2-5 (may survive in zone 6a)
Height: 21-30 meters (70-100 feet) tall, rarely to 48 meters (160 feet) tall in favorable habitats
Diameter: 3-4.5 meters (10-15 feet) wide, trunk to 90 centimeters (3 feet) wide at most
Growth Rate: Slow, growth rate maxes at 60 centimeters (24 inches) annually. First-year seedlings may be only a few inches tall, including the root system and above-ground section.
Age: may persist for 600 years, typically to 150
Root System: shallow
Subspecies: var. mexicana, var. engelmannii, ‘Argenata’, ‘Glauca’
Tolerates: herbivores (deer), harsh/cold winds, heavy snowfall, high elevations (commonly found in elevations around 11,000 feet above sea level)
Problems (major): These perform very poorly in heavy/clay soils, in regions with drought, and in warmer regions (unable to thrive in hot conditions of zone 6 and warmer). Wood rot, brown rot, oak root rot, root rot, sooty mold, aphids, and spruce budworm may be fatal.
Problems (minor): most problems major
Soil requirements: requires moist, well-drained soils, prefers slightly acidic medium soils/loams
Air requirements: performs poorly in high humidity areas, prefers cool sites with short, mild summers
Watering requirement: moderate, native to regions with greater than 60 centimeters (24 inches) of rainfall monthly
Sun requirement: These require full sun once mature, tolerates partial shade. Seedlings prefer about 50% shade for germination.
Needles: dark green to dull blue, singly attached to pegs, four-sided, to 2 centimeters (1 inch) long
Cones (male): cylindrical, purple, produced in the lower region with foliage
Cones (female): to 8 centimeters (3 inches) long, thin scales, red, initially erect, drooping at maturity
Bark: thin, scaly, reddish or purple-ish
Form: narrow, conical (cone-shaped)
Seeds require stratification: yes
Monoecious or Dioecious: monoecious
This spruce is very common in the Rocky Mountains, dominating much of the landscape above 10,000 feet above sea level. These often become windswept in areas with brutal, cold winds.
The wood is sometimes used for lumber or poles.
All of the images provided were taken by me. They may be used for educational/informational purposes only, provided that this article/online journal is appropriately cited first.