Colorado Spruce

• Colorado spruce, also called Colorado blue and blue spruce for its bluish color range, is capable of growing under a variety of soil conditions within zone 6. Zone 6 extends from the northwestern boundary of Washington state and Canada, dips through the Rocky Mountains and Colorado, stretches across the lower portion of the upper Midwest and ends along the Maine and Nova Scotia coastline. Temperatures reach lows of minus 10 degrees Fahrenheit and Colorado spruce is capable of withstanding the low range as well as drought and heat.
  
  

Arborvitae

• Arborvitae is a fast-growing evergreen often found in the landscape as a windscreen or privacy screen. The trees take on pyramidal shapes or columnar, depending on the cultivar. Some are grown alone as specimen plants. Arborvitae is capable of withstanding heavy snow and ice loads making it suitable for areas with heavy, wet snow.
  
  

Eastern White Pine

• Eastern white pine reaches heights of 150 feet and is often found in forests throughout the upper Midwest. A highly adaptable tree, it grows as far south as Alabama and Georgia. Due to its height the tree is often used for commercial purposes; for timber as well as for Christmas trees.
  
  

Yew

• Yew in general, and its many cultivars in particular, are frequently found in home landscapes. The tree takes on many forms -- from low-lying shrubs to upright, columnar trees. Yews do well when planted in slightly acidic, well-draining soils. During the winter yew trees and shrubs drop interior needles and may display yellowish foliage but in the spring a vibrant healthy green foliage will reemerge.
  
  

Norway Spruce

• Norway spruce is a fast-growing dark green evergreen that matures at heights of 60 feet. The tree works well as a standalone specimen and is also useful as a windbreak.