The Arboretum ’ s Oak Collection
B y D i r k G i s e b u r t P h o t o s b y N i a l l D u n n e
When I was a child growing up near Seattle in the ’ 60s , my family made a ritual annual stroll with my grandmother down Azalea Way in the Arboretum near the peak bloom of spring . The abundance of flowers was impressive , but what caught my eye — even as a kid — was the resplendent golden oak , Quercus robur ‘ Concordia ’, on the uphill bank . What my emotional response to this standout tree was exactly , I can ’ t recall . It is a vivid memory , though , of a vivid tree .
The Arboretum would look very different without this and the scores of other oaks in the collection . Much later in life , when I was inspired by Art Kruckeberg and wanted to figure something out about oaks , the Arboretum was one of my best teachers . I picked up the booklet , “ The Woody Plant Collection in the Washington Park Arboretum ” ( 1994 ), and scouted out all 74 taxa listed there . Just one of them , the Garry or Oregon white oak ( Quercus garryana ), is native to this territory .
THIS PAGE LEFT : Two common oaks ( Quercus robur ) from the mid- 1930s , main oak collection . TOP : Black oak ( Quercus velutina ) from the eastern U . S ., main collection . BOTTOM : Swamp chestnut oak ( Quercus michauxii ) from the Southeast , main collection .
FACING PAGE LEFT TO RIGHT : Chinese cork oak ( Quercus variabilis ), main collection . Nuttall ’ s oak ( Quercus texana ), south-central U . S ., main collection . Chinkapin oak ( Quercus muehlenbergii ), eastern and central U . S ., main collection .
The years march on . Oaks can live for centuries , but how are all these exotic species faring in our cool , sub-Mediterranean climate ? How are they functioning in the broader collection ? How is the Arboretum using them in its research , teaching and conservation roles ? What ’ s new or up-and-coming in terms of collection additions or modifications ?
Ray Larson , interim director and curator of Living Collections at UW Botanic Gardens , graciously met me over Zoom to talk about some of these questions .
Where did the original collection come from ? In terms of pure numbers , the familiar , large deciduous oaks of Eastern North America ( ENA )— such as northern red oak ( Quercus rubra ), pin oak ( Q . palustris ), and scarlet oak ( Q . coccinea )— predominate the oak collection
16 v Washington Park Arboretum Bulletin