Pacific Heritage™ Garry Oak
Quercus garryana ‘Pacific Heritage™’
Our Pacific Northwest native Garry oak, (Quercus garryana) is a popular tree, mostly recognized for the specific regions in the PNW where it stands out in the landscape. In maturity, Garry oak can become a spectacular specimen of magnificent size and structural character, which only improves with age. Within its native range, the Garry oak contributes to our sense of place. We are compelled to plant more when development in those locations has resulted in the removal of so many. The demand for nursery trees to plant can readily outpace the supply. The challenge for growers is that Garry oak is very susceptible to transplant mortality and, frankly, can appear quite gangly and unattractive in youth, two common reasons many growers avoid it. However, a select group of growers like us continue to work with it.
In recent years one of those growers, Robinson Nursery, Inc., observed what they believed to be a Garry oak cross. By process of elimination, it appears to be a cross with a nearby Heritage® oak (Quercus x macedanielii ‘Clemons’) in their nursery. In the plant world, Quercus are widely known for this easy cross pollination, and are sometimes referred to as one of our most promiscuous plants. In the midwest where I grew up, we continually thought we were discovering a new species of oak while keying out different specimens, only to realize it was a cross of two nearby different oak species that produced another unusual offspring or hybrid.
As this Garry oak and Heritage® oak cross was evaluated at Robinson Nursery, Inc., favorable characteristics emerged: vigorous growth, a strong central leader, ease of transplanting, and bright red color on emerging leaves. These traits all present improvements over the Garry oak species form.
Robinson Nursery, Inc. propagated this new tree with limited distribution, and a few production nurseries around the country, including ours, began to grow and evaluate it. We have all observed those same favorable characteristics noted above.
Throughout Urban Forest Nursery, Inc.’s production history with Garry oak, we experienced up to 50% mortality when transplanting bare root liners. There has been no transplanting losses with the new Garry/Heritage® oak cross. Garry oaks are notoriously double, triple, or no-leader trees, but the Garry/Heritage cross nearly always develops a strong single leader. And finally, the new Garry/Heritage oak trees exhibit bright red coloration on emerging leaves and easily outgrow their Garry oak relatives.
Naming and determining this tree’s lineage has taken longer than its distribution and growth. Nurseries have had these trees ready for sale without a name. This past year, a name was finally agreed upon: Pacific Heritage™ Garry Oak, (Quercus garryana ‘Pacific Heritage’ ™). This is an impressive and justifiable name given its parents and potential.
We really never know how new tree selections will perform in the long run and the true character of this tree will also take time. It can take decades to see how trees perform in terms of vigor, structure, drought, and disease and insect resilience. Although studies show that urban trees seldom last more than 10 years, we must find ways to plant and keep them alive for much longer. Longer-lived resilient trees must be in our future. The ultimate size and character of Pacific Heritage™ oak are yet to be realized. This is a tree that likely needs plentiful above and below-ground space. It should be planted first in parks, greenspaces, and wide boulevard spaces.
I enjoy the challenge of finding new trees like this and watching them grow. Let us know if you are interested in doing the same, as they are now available in the industry.
As always, let me know your experience with this tree.
ISA Certified Arborist #0135
ASCA Registered Consulting Arborist #356
Certified Tree Risk Assessor #PNW-0327