The tree on the right leans eastward in 1928 as Fuller Lodge is constructed. Courtesy/Los Alamos Historic Society Archive

Time line of history displayed over concentric tree rings speaks to tree grown, climate conditions. Photo/John Ruminer

By Sharon Snyder
Los Alamos Historical Society

Sometimes history can be found in interesting places!

For 136 years, a Ponderosa Pine grew on the Pajarito Plateau and eventually became a magnificent tree in the middle of Los Alamos. It grew while amazing events happened around it, and in all that time it kept a record of the years.

In the autumn of 2016, the tree was one of several stately ponderosas that stood near the Guest Cottage that houses the Los Alamos History Museum, but it was leaning to the east. A companion tree on the other side of the walkway was dying. Together, the two trees posed a threat to nearby structures, including Fuller Lodge. The County decided to remove them. During that process, someone had the fortunate idea to save a slice of the leaning tree to preserve its growth rings. As it turned out, those rings would take us on a wonderful journey.

A tree accumulates rings of yearly growth, and when the tree is cut down, the rings are exposed as a concentric pattern of differing widths. From those rings we can learn about changes in climate, insect infestations, and sometimes the effect of human contact by studying the growth pattern of the rings.

To learn as much as we could, the historical society welcomed the help of Dr. Tom Swetnam, Regents’ Professor Emeritus of Dendrochronology at the University of Arizona and dendrochronologist with the Jemez Mountains Tree-Ring Laboratory. Dendrochronology is the study of environmental and cultural history using tree rings. Each ring captures one year of climate history.

To help us analyze the layers of growth that appear as alternating rings of light and dark wood in our tree slice, the rings were looked at as a timeline of historical events in the past. As each ring was formed, it corresponded with a time and events in our history. Through analysis of the rings, we took an amazing journey.

In 1844, our tree was a mere sprig. Two years later, the ring that formed coincided with the arrival of Gen. Stephen Watts Kearny and his Army of the West in Santa Fe. He gave his famous speech to the residents assembled on the plaza, saying, “New Mexicans: We come amongst you to take possession of New Mexico, which we do in the name of the United States . . . .” The war with Mexico ended two years later with the signing of the Treaty of Guadalupe-Hidalgo in 1848.

More than a decade later, our country was involved in a civil war, and as the tree laid down its rings for 1861 and 1862, two significant battles of the Civil War were fought in New Mexico. In 1862 the Battle of Valverde was won by the Confederates as they fought north of Socorro and then marched north to occupy Santa Fe before losing the Battle of Glorieta Pass. That battle won by the Union Army marked the end of the Confederate presence in New Mexico.

As the ring for 1887 was forming, Juan Lewis Garcia became the first homesteader on the Pajarito Plateau, and as the ring formed for 1912, New Mexico became the 47th state of the union. Victor Romero built his cabin in 1913 as the tree laid down another ring. That cabin was destined to be moved to the lawn at Fuller Lodge, only yards from the pine tree. Three years later, the tree ring coincides with the creation of Bandelier National Monument in 1916, and a year later, in 1917, Ashley Pond founded the Los Alamos Ranch School.

The year of 1917 was one of trauma and change for the tree. The tree rings up to that date were symmetrical, but in 1917 the tree added a dark asymmetric growth pattern that showed severe damage to the outer layer. John Ruminer, chairman of the historical society’s Historic Properties Committee, surmises that the tree was wrapped with chains or cables and used with a pulley block for dragging logs during the construction of the Big House, the first building constructed at the ranch school. The tree ring pattern also indicates that the tree began to lean some 10 degrees to the east at that time. In a picture taken during the construction of Fuller Lodge in 1928, the tree (on the right) can be seen leaning toward the east.

The tree was cut down in 2016 for safety reasons, but it taught us a great deal. History is where you find it!