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1927 Map of the Arboretum

Collection Statistics

Curatorial Fellows Joyce Chery and Jordan Wood verify Amelanchier nantucketensis accessions. Kyle Port
Curatorial Fellows Joyce Chery and Jordan Wood verify Amelanchier nantucketensis accessions

Permanent Collections

As of January 2023, the permanent collections (which exclude nursery holdings) comprise 16,015 individual plants that belong to 10,452 accessions. These accessions represent 2,112 different species and 1,397 cultivars, which respectively illustrate the Arboretum’s broad biological and horticultural diversity, exceptional for a temperate woody plant collection.

The collections are considered one of the best documented in the world, especially with regard to wild provenance. Many of these lineages are of historical and botanical importance, representing the original North American introductions of eastern Asian plants collected by Arboretum staff such as Charles Sprague Sargent, Ernest H. Wilson, John G. Jack, Joseph Rock, and William Purdom.

Contemporary explorers continue a legacy of plant discovery now guided by the Campaign for the Living Collections.

Read more about the 150 years’ of plant exploration at the Arnold Arboretum.


Table 1. Taxonomic profile of the Living Collections (Includes Nursery Holdings) of the Arnold Arboretum.a

RANKNUMBER
Families115
Genera417
Species2,190
  Subspecies105
  Varieties333
  Formae61
  Cultivars1,407
Interspecific Hybrids434
Intergeneric Hybrids14
aNumbers for infraspecific ranks correspond only to those accessions where rank is known.

Table 2. Provenance of Accessions in the Living Collections (Includes Nursery Holdings) of the Arnold Arboretum.

PROVENANCETOTAL NUMBERPERCENT OF TOTAL
Wild
  Direct3,26430
  Indirecta9529
Garden2,95227
Uncertainb3,74534
aFrom a cultivated plant of known (indirect) wild origin.
bIncludes 2,599 existing or spontaneous accessions whose provenance cannot be determined.

Dead Collections

Only a minority of the accessions ever attempted to be grown in the collections of the Arnold Arboretum are currently alive—some perished on the grounds, while others representing propagules (e.g., seed, graft, cutting) may have never grown to maturity. The records associated with these legacy collections hold immense value in documenting the history of plant introductions, since the Arboretum facilitated the initial point of entry in North America for many species.

As of January 2023, the legacy collections comprised 98,235 accessions representing 22,046 taxa (kinds). Of these, 69,224 individual plants belonging to 45,941 accessions representing 13,523 taxa (kinds) were inventoried within the living collections (which include nursery holdings) before perishing.


Table 3. Taxonomic profile of the Legacy (Dead) Collections of the Arnold Arboretum.a

RANKNUMBER
Families 260
Genera 1,603
Species 12,117
  Subspecies 331
  Varieties1,713
  Formae 314
  Cultivars 8,647
Interspecific Hybrids 1,689
Intergeneric Hybrids 102
aNumbers for infraspecific ranks correspond only to those accessions where rank is known.

Table 4. Provenance of the Legacy (Dead) Accessions of the Arnold Arboretum.

PROVENANCETOTAL NUMBERPERCENT OF TOTAL
Wild
  Direct 18,190 18
  Indirecta 5,519 6
Garden 31,574 32
Uncertainb 42,952 44
aFrom a cultivated plant of known (indirect) wild origin.
bIncludes 1,644 existing or spontaneous accessions whose provenance cannot be determined.