Western White Pine State Tree of Idaho

The state tree of Idaho is the Western White Pine (Pinus monticola). This conifer is also known as mountain white pine, Idaho white pine, and silver pine. The great stands of western white pine inhabit the Pacific Northwest. The trees are hardy in Zones 5 through 7, but are sometimes found in colder climates.

This pine tree can grow to a height of 200 feet with a diameter of 4-8 feet. There are trees that live to be well over 400 years old. When the trees are growing close together, the lower branches are shed, leaving the appearance of long clean poles. There are dark rings visible on the trunk to indicate where the branches were. These pines do not tolerate shade well.

This conifer prefers sandy or loamy soil and lots of sun. The trees grows well in acidic or neutral soil, even if the soil is nutrient deficient. When planted in a landscape area, the 26 foot spread of the lateral roots should be accommodated.

The western white pine is monoecious having both male & female cones. The cones are 5-12 inches long and can appear in clusters of up to five cones. The female cones are valued for their decorative appearance.

Western white pine is harvested commercially for cut lumber and can be found in the production of doors and windows sashes. When wooden matches were common, this pine was the preferred wood source.

Animals in the pine forests use the white pine for cover and nesting sites. The seeds are a food source for small animals. The leaves and branches are not a favorite for eating if other foods are available.

The white pine bark was used by the early people in making baskets. They also used the spring sap in their meal preparation. There is nutritional value in the inner bark which could be used as a thickener. There is some evidence of medicinal uses for the sap, pitch, and bark.

The trees are propagated from seed. In managed forests, seedlings are then transplanted to the forest location. Transplants have a better survival rate if they are planted early in their growth cycle and protected through the first winter. Survival is better if competing ground cover is cleared or if a heavy mulch is applied.

This conifer has predators. The trees can be attached by rust, fungi, root diseases, insects such as the pine beetle. The trees are also sensitive to drought conditions.

Sources
Pinus monticola, US Forest Service, http://www.fs.fed.us/database/feis/plants/tree/pinmot/all.html
Pinus monticola, Plants for a Future, http://www.pfaf.org/database/plants.php?Pinus+monticola
Pinus monticola, North Carolina State University, http://www.ces.ncsu.edu/depts/hort/consumer/factsheets/trees-new/pinus_monticola.html
Western White Pine, Virginia Tech, http://www.cnr.vt.edu/dendro/dendrology/syllabus/factsheet.cfm?ID=230