Colorado Blue Spruce

In the summer of 1872, mere months after the Arnold Arboretum had been established, Harvard botanist Asa Gray embarked on a cross-country trip with his wife, Jane Loring Gray. The trip was enabled by the recently completed Pacific Railroad, which connected the eastern and western rail networks. Gray would disembark, at station stops, to examine plants along the way. On the return trip, the Grays made a special diversion in central Colorado. There, they met with a physician-turned-botanist named Charles Christopher Parry. Although Parry was based in eastern Iowa, he had spent much of the previous two dozen years botanizing in the western United States. In 1861, Parry had made the first documented ascent of one of the peaks—the tenth highest in the Rocky Mountains—and named it after Asa Gray. The Grays were there to see Parry and to summit Grays Peak. 

A few weeks later, Parry wrote to Gray, who had returned to Cambridge, promising that seed was on the way. “I shall have to attend to the conifers this week,” he wrote. “I think now of shipping the cones in heavy ore sacks containing about ½ bushel.” While it seems reasonable that the seed would have been destined for the newly formed Arboretum, the first shipment from Parry wouldn’t appear in the Arboretum records until 1873, with more shipments to come.  

In September 1874, Parry wrote to Gray, from Denver. He noted that a box of plants had been sent to the Harvard Botanic Garden, in Cambridge. A collection of seedling spruces had also been included for the Arboretum. Seeds would follow. “No time just now to answer Mr. Sargent’s inquiries,” Parry wrote, naming Charles Sprague Sargent, the botanical newcomer who had been appointed to the head of the Arboretum. This Colorado spruce (Picea pungens), along with three others (accessions 1476 and 22808) growing nearby, arrived among that seed shipment in 1874. 

From afar, this Colorado blue spruce—a sentinel on the edge of Kent Field—looks like an architectural sketch. The branches are sparse and lean, hewing close to the ramrod-straight trunk. The tree is nothing like the young, dense landscape specimens of this species; rather this tree, as with its neighbors, look untrammeled, untamed. Sargent noted this, too, when he wrote about the species in the 12th volume of his Silva of North America, published in 1897. “The feeble growth of the lower branches on the oldest trees in cultivation, now thirty or forty feet in height, show that those branches will soon perish, and that Picea Parryana [the name Sargent had coined for the species], although charming in its early years, is less well suited to become a permanent ornament of parks and gardens than trees which, producing more vigorous lower branches, maintain to old age the conical form, perfect from the ground up.” 

Sargent could have been commenting on these very trees, or perhaps older trees growing at the Harvard Botanic Garden. In 1863, Parry had provided seeds of this species—then unnamed by botanists—for Gray to grow at the garden. The botanist George Engelmann named the species, in 1879, based on one of Parry’s collections.

Parry would later accompany both Sargent and Engelmann on a collecting trip to the West Coast in the summer of 1880. It was a rushed journey, and an undercurrent of exasperation comes through Parry’s account of the trip. In a letter to Gray, Parry described “the hurry & push of Sargent.” To a veteran collector, it must have been obvious that the work of field botany would never be completed on a summer trip, nor even in a lifetime. Parry’s specimens at the Arboretum now stand as steadfast reminders of his botanical tenacity—the desire to return to the mountains again and again.  

Visiting the Arboretum’s landscape with your family to see this tree for yourself? Download a printable guide in English or Spanish.