ST. PAUL, Minn. (3/7/2011) —Conifers are planted as shelterbelts, windbreaks, living snow fences and winter wildlife thermal cover on farms and in other rural areas. They bear cones and are sometimes called evergreens.
The U.S. Postal Service issued four "Holiday Evergreens" stamps for the 2010 holidays. Many people have asked University of Minnesota Extension if the trees shown on those stamps can all be grown in Minnesota. The answer is yes.
Let's review some important characteristics for each of the conifers featured on the stamps:
Eastern Red Cedar is native to the southern half of Minnesota, hardy to zone 3b. Trees are small to medium in height, 25 to 50 feet tall with trunk up to 24 inches in diameter. Foliage can be prickly or sharp, scale-like shaped needles. Red cedars thrive in poor soils. They provide erosion control, cover for wildlife and are used for windbreaks. They can aggressively move into pastures, edges and grass plantings, but can be controlled by cutting the stump close to the ground. Berry-like cones are consumed by birds and wildlife which disperse the seeds. Aromatic, rose-colored wood is strong and used for cabinets and chests.
Blue Spruce was introduced from the central and southern Rocky Mountains, and is hardy to zone 3a. Trees are medium to large, 30 to 60 feet tall with a trunk up to 36 inches in diameter. Needles are 1/4 to 1 1/2 inches long with sharp tips. Color can vary by tree from green, bluish-green or silver-blue. Cones are 2 to 4 inches long. Blue spruce is shade-tolerant, slow-growing and long-lived. Mature trees can be disfigured or killed by cytospora canker or rhizosphaera needlecast disease. A recommended spruce which is tolerant of these diseases is the white spruce (Black Hills spruce). Black Hills spruce is used in ornamental and shelterbelt plantings.
Ponderosa Pine is an introduced species from western North America, hardy to zone 3b. Trees are large, 40 to 70 feet tall (or taller) with a trunk up to 48 inches in diameter. Needles are 5 to 8 inches long, 2 or 3 per bundle, stiff and dark green. Cones are 3 to 6 inches long. These trees are moderately fast-growing and long-lived; however, they do not tolerate shade.
Balsam Fir is native to northeastern and southeastern Minnesota, hardy to zone 3a. Trees are medium, 40 to 75 feet tall and trunk 18 inches in diameter. Needles are linear-shaped, 1/2 to 1 inch long and shiny green. Cones are 2 to 4 inches long, erect, and purple to purplish-brown. Trees are shade-tolerant, slow-growing, and popular for Christmas trees and decorative crafts. They do not perform well in the hot, windy and dry locations in Minnesota.
Trees can be purchased from nurseries or County Soil and Water Conservation Districts (SWCD) that sell trees for spring planting.
When identifying trees to plant in your landscape, refer to Extension's "My Minnesota Woods" forestry website at www.extension.umn.edu/go/1057 for helpful tree selection information.
Any use of this article must include the byline or following credit line:
Gary Wyatt is an agroforestry educator with University of Minnesota Extension.
Media Contact: Catherine Dehdashti, U of M Extension, (612) 625-0237, firstname.lastname@example.org