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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 2020, the permanent collections (which exclude nursery holdings) comprise 15,413 individual plants that belong to 10,285 accessions. These accessions represent 2,043 different species and 1,411 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
Families112
Genera397
Species2,192
  Subspecies103
  Varieties328
  Formae65
  Cultivars1,428
Interspecific Hybrids431
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
  Direct3,27129
  Indirecta9208
Garden3,00027
Uncertainb3,89436
aFrom a cultivated plant of known (indirect) wild origin.
bIncludes 2,666 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 2020, the legacy collections comprised 76,785 accessions representing 18,404 taxa (kinds). Of these, 67,216 individual plants belonging to 44,797 accessions representing 13,288 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 220
Genera 1,268
Species 10,304
  Subspecies 298
  Varieties 1,525
  Formae 291
  Cultivars 7,084
Interspecific Hybrids 1,533
Intergeneric Hybrids 100
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 14,835 19
  Indirecta 4,387 6
Garden 22,858 30
Uncertainb 34,705 45
aFrom a cultivated plant of known (indirect) wild origin.
bIncludes 1,509 existing or spontaneous accessions whose provenance cannot be determined.