July 20th, 2016
Also known as Blue Spruce, Colorado Blue Spruce
Identification
Colorado Spruce have short, sharp, square, singular, and stiff needles. One of the easiest ways to pick out a Colorado Spruce is to shake hands with it! The prickly needles are not particularly welcoming and stand out from other spruce trees for their bluish colour. They grow at a slow to medium rate, growing to be about 50 - 75 feet tall with a spread of 10 to 20 feet when they are mature. They are long living, typically getting to be 50 – 100 years old. The needles of this tree grow in whorls and last for three to four years, after which they then turn yellow and fall from the tree. Colorado Spruce produce two to four inch brown cones that require one year to mature, and fall to the ground in autumn. Their bark is a platy cinnamon colour and their buds are brownish yellow.

Disease Susceptibility
Young seedlings need protection from the sun because they are susceptible to damage to their tissues caused by excessive sunlight – this is called sun scald. Otherwise, Colorado Spruce are rarely affected by pests. Cytospora canker may attack lower branches as the tree matures. Infestations of red spider mites and yellowheaded sawfly can occur, along with spruce gall aphids. These trees may also contract pine-needle scale.
Best Care Practices
Colorado Spruce do best in sunny locations with moist, well-drained soil. They will tolerate wind and can adapt to dry soil. These trees withstand wind better than many spruce trees, due to their wide-spreading and somewhat deep root systems. They do not like dry or acidic soil and will grow, slowly, in full shade. They generally grow slowly for the first five years after planting, but grow from 20 - 60 cm annually thereafter. These trees are commonly used in Alberta for inside rows in shelter belts (rural rows of trees used for blocking wind). Animals usually only use these trees for food during shortages since their needles are so sharp.

Interesting Facts about Colorado Spruce
- Colorado Spruce are native to the Rocky Mountains in the Western United States and are the most widely planted variety of Spruce.
- Their Latin name is Picea pungens.
- Traditionally, Native Americans used the twigs of this tree as a gift to bring good fortune.
- This tree was discovered in 1862 in the Rocky Mountains.