by Jan Cashman
This time of year, most trees in our landscapes are leafless and brown, so we appreciate more our large evergreens. The most common upright evergreen planted here is the familiar Colorado spruce, sometimes called “blue spruce”. Pines (Pinus) have longer, greener needles than spruce, are faster-growing, and, therefore, make good specimen trees in our landscapes.
There are at least 77 species of pine trees grown in U.S. nurseries. A number of them, such as Monterey pine and Mexican pinyon pine are not hardy for our Northern climate. Eastern white pine is native to the northeastern U.S. but planted here It may winterburn; it needs more humidity and less sun in the winter than our climate provides. The hardy, native lodgepole pine does not make the best landscape tree because of its tall, thin shape and tendency to lose its lower branches. Other pine species, such as Ponderosa, Austrian, and Bristlecone, thrive in our climate and make pleasing additions to our landscapes, especially during our long winter months.
Austrian Pine is one of the most popular pines planted here, popular because of its deep green needles, rapid growth and dense shape. It was introduced to the U.S. from Europe in 1759 and has been planted extensively in the northern half of the U.S. since then. The tree’s mature height is only 30 to 40 feet. Unlike some of the other pines, Austrians keep their branches and fullness all the way to the ground as the tree grows. They tolerate our alkaline soils.
Ponderosa Pine, although not native right here in the Gallatin Valley, is the state tree of Montana. This large pine can grow to over 100 feet. Ponderosa pines tolerate poor, alkaline soils and dry conditions. Ponderosa pines that come from east of the continental divide seem to grow better in this valley than those with their source west of the divide. Thirty-five years ago we had the foresight to plant a grove of Ponderosa pines south of our house to give us a noise and visual screening from busy Springhill Road. Ponderosa pines have big, attractive pinecones good for Christmas decorating.
Scotch Pine, as you might guess, are native to Scotland and Northern Europe. At maturity, this fast-growing pine can reach 50 to 100 feet tall. Their growth habit is irregular and open, sometimes eerie-looking against the sunset. Scotch pines are often used for bonsai. The bottom branches of Scotch pines tend to die and drop as the tree matures. Plant breeders such as Iseli Nursery in Boring, Oregon, have developed some new and unusual-shaped Scotch pines for the plant enthusiast, some tall and thin, others dwarfed and spreading. Unfortunately, during the Western pine beetle outbreak some years ago, we lost many Scotch pine.
Limber and Swiss Stone Pine are two often overlooked pine trees. The native, hardy limber pine is a small, slower growing tree with an interesting shape. Swiss Stone pine, also slow growing, is tall with a pyramidal shape. Both are resistant to winter-burn and tolerant of harsh, dry conditions.
Tannenbaum and Bristlecone Pines These two slow-growing evergreens have become popular for local landscapes because they are smaller. Tannenbaum is an upright type of mugho pine that stays small (15 feet), named Tannenbaum because it is nicely shaped like a Christmas tree. Bristlecone pines over 4000 years old are found native in the Sierra Nevada mountains, some of the oldest living organisms on the planet. This hardy, irregular-growing tree makes an interesting addition to your landscape.
Winter Protection Fence pines from deer who love to munch on their needles. Even the hardiest of evergreens, especially those newly planted, can winterburn where the needles turn brown and dry from winter wind and sun. Protect your evergreens by spraying Wiltpruf, an organic antidesiccant, on the needles in the fall or erect a shade on the southwest side by stretching burlap between posts. Deep water your pines and other evergreens in November before the ground freezes and again anytime winter weather is warm and dry.
Pines provide deep green color and interesting architectural form to your landscape. Most are hardy and easy and fast to grow. Plant one or a grove of them. Then hang Christmas lights. You will be glad you did.