The green spruce tree, or Picea pungens, is a type of evergreen tree with a pyramid shape and blue-green or dark green needles. It is also known as a blue spruce or a Colorado blue spruce. Green spruce trees are often slow growing but can reach a great height and width once mature. The tree is native to the United States and reproduces with cone-shaped fruits.
The green spruce tree is an evergreen, so its foliage does not change color with the seasons, nor does it lose needles as the temperature drops. Typically, the needles are about 1.25 inches (3.17 cm) long. The color of the needles can be a dark green, blue-green, or silver blue. The needles on the tree are very stiff and pointed. As the needles are very sharp, they can cause injury if handled with bare hands.
Usually, a green spruce produces 3-inch (7.62-cm) cones. In some cases, the cones can be as long as 5 inches (12.7 cm). Most cones are narrower at the top and bottom. When first forming, the cones are green or purple in color but turn brown as they mature. The scales on the cones are usually thin and wavy.
Left alone, the tree will grow to a great height. Some trees can reach 120 feet (36.58 m) tall. The usual height is between 30 and 60 feet (9 and 18 m). At its widest point, the tree is usually 10 to 20 feet (3 to 6 m) in diameter. Some varieties of spruce are cultivated to grow to a specific height and width. For example, the "Fat Albert" variety usually grows to 15 feet (4.57 m) tall. It has a wide, round shape, especially when immature.
Green spruce trees are native to the western United States, particularly to the state of Colorado. They are hardy to zone two and can survive in up to zone seven. The tree needs moist soil and full sun to thrive. Depending on the variety, it may be able to tolerate drought conditions.
Usually, the trees are planted to serve as a windbreak or a privacy screen. Large varieties can serve as the focal point on a lawn and can provide shade in hot weather. Some homeowners plant the trees as a foundation planting. Unless a dwarf variety is planted, the spruce will likely grow too large, potentially damaging the foundation of a house.