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Carya illinoinensis

Accession Number
The alpha-numeric value assigned to a plant when it is added to the living collection as a way of identifying it.
Accession Date
The year the plant’s accession number was assigned.
Common Name
The non-scientific name for the plant.
Scientific Name
The scientific name describes the species of an organism. The first word is the plant's scientific genus and the second is the specific epithet. This two-word binomial is sometimes followed by other taxonomic descriptors, including subspecies (denoted by "ssp."), variety (denoted by "var."), form (denoted by "f." or "forma"), and cultivar (denoted by single quotation marks).
Plant Family
The family to which the plant belongs.
Propagation Material
The first part (material code) describes the material used to create the plant. The most common codes are "SD" (seed), "EX" (existing plant), "PT" (plant), "CT" (cutting), "SC" (scion), "SG" (seedling), and "GR" (graft). The second part describes the lineage the plant is derived from. The last part describes the year of propagation.
Collection Data
The first part indicates provenance (place or source of origin) using a letter code ("W" = wild, "G" = garden, "Z" = indirect wild, "U" = uncertain). The second part lists the plant source. For wild-collected material, the collector, collection number, and country are given.
The location of the plant on the landscape.
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Carya illinoinensis
SD - LINEAGE 12913

This pecan, collected in 1882, arrived from the first large research project undertaken at the Arnold Arboretum.

In 1879, Charles Sprague Sargent was a mere seven years into his career at the Arnold Arboretum. He had been appointed curator in 1872 and director in 1873, and by 1879, roadways and initial plantings at the Arboretum had yet to be installed. So, when Sargent was named to lead a massive forest inventory for the 1880 United States census, he had good reason to hesitate. Nonetheless, after deliberation, he agreed. Sargent recognized that the census would give him an unprecedented opportunity to visit forests across the country—in turn, strengthening the collections of the Arboretum. 

This ambitious project culminated in 1884, when Sargent published the Report on the Forests of North America (Exclusive of Mexico). In this report, Sargent aimed to describe the composition of forests across the country. Significantly, the publication included maps of the distribution of individual species and genera. These maps are considered the first attempt to render plant distributions on a large scale. Sargent travelled across the continent for the project, but given the scope of the undertaking, he needed assistants. He officially appointed botanists as “special agents,” and others provided unofficial contributions. 

One of these unofficial correspondents was Robert Ridgway, a young naturalist from IllinoisIn 1880, Ridgway had been appointed the first full-time curator of birds at the United States National Museum. Although Ridgway was based in Washington, DC, he continued to study the landscape of Illinois—his home state—while he prepared a two-volume treatise on the birds of the state. His research on woodlands in southern Illinois (and adjacent portions of Indiana) far surpassed the needs of the census, and Sargent encouraged him to publish his findings “in toto.” The article ran 40 pages in the Proceedings of the United States National Museum, published in 1882. In the same year, the Arboretum received seed shipments from Ridgway, including seed for this very pecan. 

[The pecan] is by far the largest of the hickories, being, in truth, one of the very largest of the forest,” Ridgway wrote in his report. He noted that the pecan’s “altitude and majestic appearance” was unrivaled within the forests flanking the Wabash River, the riverine border between southern Illinois and IndianaBut one of the largest specimens175 feet highwas only measured after it had been felled, suggesting broader landscape pressures. “Originally, much the larger part of the district under consideration was heavily timbered,” Ridgway wrote. “Since the first settlement of the country, however, the distribution of the timber has very materially changed, much of the original forest having been cleared for cultivation.” 

Sargent became increasingly interested in hickory taxonomy almost three decades later. At that point, he once again wrote to Ridgway, asking for information. Ridgway responded, in 1912, with characteristically meticulous and detailed handwritten notes. “I have long been convinced that the genus is in sad need of overhauling,” he wrote, “and feel sure there are several more good species than are recognized in the books.” This pecan now stands as a testament to a long-standing botanical relationship—and to national collaboration that helped to establish the Arnold Arboretum. 


Viewing this plant in-person? Look for these defining characteristics:

  • 1
    Bark of pecan
    Furrowed bark. Jonathan Damery
  • 2
    Form of mature pecan
    Straight trunk. William (Ned) Friedman
  • 3
    Green pecans held in hand
    Fruits chewed and dropped by squirrels. Jonathan Damery

About Our Collection

Fun Facts

  • The native range of the pecan is centered in Arkansas, Oklahoma, and Louisiana, with its northernmost populations occurring in northwestern Illinois and northeastern Iowa.

  • According to the U.S. Census of Agriculture for 2017, more than 19,000 farms reported growing pecans. Among nut crops in the United States, only almonds outproduced pecans in terms of acreage.

  • “The Pecan, with its tall straight trunk and great head of cheerful yellow-green foliage, is one of the most impressive trees of eastern North America,” Charles Sprague Sargent wrote in 1895.

  • According to botanists, fruits of hickories are not true nuts—rather “drupe-like nuts,” or trymata (singular: tryma).


Living Specimens
Specimens Dead or Removed
First Addition
Most Recent Addition
Tallest Specimen

Living Specimens

Plant ID Accession Date Received As Origin Source

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