Oaks are among the most diverse and dominant trees in North America, so the genus Quercus was a natural choice for the first multi-institutional Plant Collections Network collection. After almost two years of planning and coordination on the part of Dennis Collins, Curator of Plant Collections at the Mount Auburn Cemetery, 15 gardens with large oak collections were inducted into the Plant Collections Network in August of 2007.
A newly-formed Oak Curatorial Group with representatives from all gardens is taking on these important challenges. Starhill Forest Arboretum joined the Quercus Multisite Collection in 2009, and Donald E Davis Arboretum at Auburn University joined in January 2010. These were followed by Bartlett Tree Research Laboratories Arboretum and Gabis Arboretum at the end of that year, with the latest addition of Boyce Thompson Arboretum in 2012.
Although the focus of the individual collections ranges from botanical and horticultural research to ornamental display, all of the institutions are committed to germplasm conservation and recognize the advantages of working collectively rather than independently. The genus Quercus has been estimated to contain over 500 naturally-occurring taxa which are distributed throughout the northern hemisphere in a broad variety of climate zones and habitats. It would be virtually impossible to develop a comprehensive collection of oaks at a single garden due to climatic constraints. Having a multi-institutional collection with gardens in a variety of climate areas expands the possibilities for maximizing the representation of oak diversity. California, the Pacific Northwest, the Midwest, and the Northeast are already represented by gardens in the group. One of the goals for the group is to expand and recruit gardens in the Southeast, the Southwest desert regions, and Mexico in order to improve our representation of oaks from those regions. In addition to collaborating on expanding the group's representation of oak diversity, the collection holders are also working together to raise standards for curatorial management, to promote research use of the collections, to interpret the value and importance of oaks to garden visitors, and to identify and help solve taxonomic problems.