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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 September 2022, the permanent collections (which exclude nursery holdings) comprise 16,003 individual plants that belong to 10,449 accessions. These accessions represent 2,115 different species and 1,401 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
Families114
Genera416
Species2,194
  Subspecies105
  Varieties334
  Formae61
  Cultivars1,410
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
  Direct3,27230
  Indirecta9579
Garden2,96627
Uncertainb3,73734
aFrom a cultivated plant of known (indirect) wild origin.
bIncludes 2,586 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 September 2022, the legacy collections comprised 98,066 accessions representing 22,037 taxa (kinds). Of these, 68,974 individual plants belonging to 45,824 accessions representing 13,496 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 12,119
  Subspecies 331
  Varieties1,709
  Formae 314
  Cultivars 8,642
Interspecific Hybrids 1,687
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 18,142 18
  Indirecta 5,500 6
Garden 31,520 32
Uncertainb 42,904 44
aFrom a cultivated plant of known (indirect) wild origin.
bIncludes 1,606 existing or spontaneous accessions whose provenance cannot be determined.