Please join the Willamette Valley Hardy Plant Group on Tuesday, September 9, 2025 at 7:00 PM in the Unitarian Universalist Church, 1685 W 13th Ave, Eugene OR, for our guest speaker Dr. Peter Del Tredici.

Dr. Del Tredici will discuss urban ecosystems as the ultimate manifestation of the dynamic interaction between humans and nature—between our desire for neat, orderly landscapes on the one hand and our fear of messy ecological chaos on the other. This presentation will focus on the plants—both native and non-native—that grow without cultivation in cities and their remarkable ability to flourish in spite of stressful environmental conditions. Cities—along with the plants and animals they support—can be considered "novel" ecosystems that not only reflect a tumultuous past but also preview our unpredictable future. The spontaneous vegetation that inhabits our cities is as cosmopolitan as its human population and, quite frankly, better adapted to their changing environmental conditions than the native species that once grew there. Like it or not, these novel ecosystems have become the new normal and people need to recognize that they not only help make our cities more livable but also help clean up the mess we have made of the planet. Learning how to manage them to increase their aesthetic and ecological value is both a challenge and an opportunity for gardeners and professional horticulturists.

Dr. Peter Del Tredici is a botanist specializing in the growth and development of trees. He retired from the Arnold Arboretum of Harvard University in 2014 after working there as a plant propagator, editor of Arnoldia, Director of Living Collections and Senior Research Scientist for 35 years. He taught in the Landscape Architecture Department at the Harvard Graduate School of Design for 24 years and the Urban Planning Department at MIT for three years. He has published over a hundred scientific articles on a wide variety of subjects including: the taxonomy and cultivation of hemlocks and Stewartias; the history of plant introductions from Japan and China; the ecology and evolution of the Ginkgo tree; and the morphology of basal sprouting (resilience) in trees. Since 2004, his research has focused on urban ecology and climate change, and in 2010 he published the widely acclaimed, Wild Urban Plants of the Northeast: A Field Guide (Cornell U. Press, 2010; 2nd ed. 2020). In 2013, he was awarded the Veitch Memorial Medal by the Royal Horticultural Society in recognition of his contributions to “the science and practice of horticulture.”

For more information about the group or this event, visit our website at www.thehardyplantgroup.org/events or email us at info@thehardyplantgroup.org.

Doors on the east side of the building open at 6:30 PM for refreshments, botanical sample browsing and socializing. Admission is free for members and $5 for non-members.

Membership in the Hardy Plant Group is open to all and is only $30 annually. There is ample parking in the parking lot which can be accessed from both Chambers St or W 13th Ave, with additional parking in the adjacent Looking Glass Center parking lot to the north, but please do not park under their covered entryway. Overflow parking is also available in the first 20 spaces on the east and south side of Redeemer Fellowship Church just across Chambers St to the west. View parking map at www.thehardyplantgroup.org/contact

This in-person meeting will also be broadcast live over Zoom to members who are unable to attend in person. The Zoom broadcast will also be recorded, with a viewing link sent to members to watch within two weeks of receiving the link. If you are interested in watching our Zoom broadcast, and not a member, please see the “About” page on our website.

The Willamette Valley Hardy Plant Group is a non-profit, 501(c)(3) volunteer organization for gardeners of all experience levels. The Group is dedicated to educating the community about perennials, shrubs, and other plants for use in the garden, sharing each other’s gardens, and fostering a love of gardening.