Ponderosa Pine—Or maybe you call it Bull Pine, Black Jack, Western Yellow Pine, or One of Many Other Names

Three subspecies have been identified through-mitochondrial DNA.

What a surprise! The ponderosa pine is one of the first trees with a distribution in most of the WESTERN part of the US and part of Canada! According to National Audubon Society Field Guide to North American Trees (Western Region,1980) this is the most widely distributed pine in the United States. Its range includes British Columbia. In Colorado the species covers about 2 million acres. The Colorado State Forest Service website, also says this is about 8 % of the forested area of the state. Ackerman mentions the tree grows from about 4600-9600 elevation. (Flora of Colorado, 2015.)

Like many of the other trees discussed in this blog, the ponderosa pine appears to be a  complex species. Even its “discovery” may be controversial with some sources citing 1820 and others mentioning 1805 passages from Lewis & Clark Expedition. According to the Gymnosperm Database, three subspecies have been determined through mitochondrial DNA. The three varieties appear to have geographic distinctions, too. The groupings include the northernmost trees, Pacific trees, and the more interior trees. Chris Earle, the author of conifers.org, indicates there does not seem to be interbreeding where the northern family shares habitat with the Pacific group.

This species are normally tall, straight trees with the trunk free of lower branches. OLYMPUS DIGITAL CAMERA

The Ponderosa pine is one of the three highest producing lumber species in the western United States. Its wood is used for everything from veneer to construction. Apparently the trunks were sometimes used as flagpoles as at least one story of the origin of the name Flagstaff in Arizona, involves a ponderosa pine displaying the US flag.

Ponderosa pine needles showing length and the bundles of two

The ponderosa pine provided Native Americans with food, medicine, and transportation in the form of canoes or snowshoes, as well as construction material and dyes. Almost the entire plant could be eaten. The many medicinal uses included the usual ointment for infections, skin conditions, and pain control. A less commonly mentioned use of tree parts in medicine was needles being tools for dermatological and gynecological reasons. The rosin left over after turpentine distillation is used on violin bows.

Monumental Trees lists the oldest ponderosa, located in Yosemite, to be more than 1020, although a 1914 record of a tree in southwest Colorado was measured at 1047 years. As might be expected for a tree that is only native to North America, the United States also has the widest and tallest trees. The record for height is a tree in Oregon measured to be over 268 feet tall.

At least four species of Ips beetle can infect ponderosa pines. These beetles normally attack dying or stressed trees, but when there are excess beetles they may attack and kill healthy trees. For the eighteen years from 1996 to 2014, the mountain pine beetle damaged over 3 million acres of trees in  Colorado alone. Although these beetles have always destroyed some trees, according to the National Park Service recent outbreaks had become more severe. According to the Colorado State Forest, though, the problem may have begun to abate in 2017. In the past, long term cold snaps killed off many of the noxious beetles, but with warmer winters, good forestry management techniques must be employed, including thinning of trees, and solar treatment of logs from downed trees to help control the destructive insects. With climate change, the forests of the West, as well as the rest of the world, may be changing.

The Ponderosa pines on the Fort Collins Self-guided Tree Tour are easy to find. They still sport the rustic signs first used to identify the trees.

The appearance of the bark changes as the tree ages

To find  C152 Ponderosa Pine (Pinus ponderosa), drive to the west end of Oak Street, just east of the intersection with Bryan Street. The trees are in front of the pottery studio.