December Storm Generates Loss and Renewal at Arnold Arboretum

On December 18, more than two inches of rain and wind gusts exceeding 50 miles per hour wreaked significant damage to trees in the Arnold Arboretum. Nearly 40 accessioned plants were lost across the landscape, many uprooted or—in the case of nearly a dozen hemlocks—snapped in half. While the storm was formidable in terms of tree loss and the enormity of the continuing clean-up effort, the immediate and coordinated response of the Arboretum’s horticultural team ensured safety for visitors and renewal for the plants either lost or severely compromised. It was an unusual event in many respects, breaking records for highest minimum and maximum temperature for the day and generating some of the strongest winds—outside of thunderstorms—seen in Boston in a decade. “When intense wind is accompanied by heavy rain—which softens the ground and further compromises the ability of older or compromised trees to anchor themselves—we tend to see the most damage inflicted on the collections,” said Rodney Eason, Director of Horticulture and Landscape.


Bridle Path Reimagined: 2023 Hunnewell Internship Project

The following article was originally published on the Arnold Arboretum's website, and has been republished on with permission from the arboretum. The 2023 cohort of Hunnewell horticulture interns at the Arnold Arboretum of Harvard University spent some of their summer restoring and renewing a historic pathway between the Hunnewell Building lawn and Leventritt Shrub & Vine Garden. The Arboretum’s first bridle path, named so because it was created as a thoroughfare for horseback riders, was laid out in 1928. Over the past century, as institutional priorities shifted, maintenance and use of the path declined. Revitalizing the bridle path offered the interns the opportunity to improve visitor access, restore areas damaged by poor traffic control, and re-envision planting designs to align with the Arboretum’s current curatorial practices.


Renewing Olmsted’s Promise with New Arborway Entrance at Arnold Arboretum

A recent forum at Weld Hill explored the history, philosophy, and future of the Arboretum’s entrances. A gate is much more than a piece of infrastructure. It’s also an archetype, and an ambivalent one—a portal that’s also a barrier, an impediment masquerading as an entrance. The Arnold Arboretum features nineteen entrances situated around its three-mile perimeter—entryways to the landscape that come in a variety of shapes and sizes, from backyard stiles in Roslindale to the broad, swinging, wrought-iron gates that open on the Arborway and South Street. The Arboretum’s Entrance Improvement Project seeks to renew and improve the Arboretum’s many entrances to provide a safe, accessible, and welcoming experience for all visitors.


Arnold Arboretum August Events: Caterpillar Lab, Meditations, Hikes and More

The Arnold Arboretum is a living, breathing, event-holding tree museum. There are numerous events in August at the arboretum -- and they're all free. Here is a list of the events:
Meditation Mondays
Every Monday in August, 6:30 pm
Unwind with this weekly evening meditation under the shade of the maple collection. Facilitator Bob Linscott will guide the group through 30 minutes of mindfulness and meditation designed to help you de-stress and connect with the natural world. FREE.


Plant Hardiness Zone Maps and the Arnold Arboretum

This article was originally published on the Arnold Arboretum's website, and has been republished here with permission from the Arnold Arboretum. Picking the right plant for the right spot requires getting into the “zone.” Professional horticulturists, nursery operators, and home gardeners alike rely on plant hardiness zone maps to help them choose plants with the best chance of survival in their regions. Over the past century, the Arnold Arboretum and the United States Department of Agriculture (USDA) in particular have produced maps charting estimations of plant hardiness which have been periodically revised to reflect on-going changes in environments due to global warming and climate change. The story of hardiness zones begins at the Arnold Arboretum. In 1927, Arboretum taxonomist Alfred Rehder published the Manual of Cultivated Trees and Shrubs Hardy in North America.


The Arnold Arboretum and the Legacy of Slavery

The following was written with contributions by Jon Hetman, Lisa Pearson, and William (Ned) Friedman on behalf of the Arnold Arboretum community, and originally published on the arboretum's website. It has been republished here with permission from the Arnold Arboretum. In spring of 2022, Harvard University President Larry Bacow shared the findings of the Presidential Committee on Harvard and the Legacy of Slavery, a major initiative focused on researching and day-lighting connections between Harvard and its community to both the institution and economy of slavery. Among the Committee’s findings associated with the Arnold Arboretum is a major benefactor who made his fortune trading goods produced by enslaved people, the institution’s historical connections to the Atkins Institution in Cuba, and the close ties of some instructors at the Bussey Institution to the eugenics movement. At the Arnold Arboretum, we welcome this opportunity to better understand our past as important historical context in our efforts to make our landscape more welcoming and enriching to everyone.


Eye Candy at the Arnold Arboretum

“Rarely if ever before have the Arboretum Laurels (Kalmia latifolia) been as full of flower-buds as they are now, and by the time this bulletin reaches its Massachusetts readers many of the plants will be covered with flowers. The flowering of the Laurels is the last of the great Arboretum flower shows of the year, and none of those which precede it are more beautiful, for the Mountain Laurel, or the Calico Bush as it is often called, is in the judgment of many flower-lovers the most beautiful of all North American shrubs or small trees.”

So wrote Charles Sprague Sargent, the first director of the Arnold Arboretum, in June of 1916. 107 years later, I am watching the best mountain laurel bloom in my thirteen springs here. I found a couple of very old postcards that depict the mountain laurels at the peak of their collective bloom, a seemingly endless stretch of whites, pinks, and even reds at the base of Hemlock Hill. The upper image is from circa 1915, showing the Olmsted designed carriage road with its graceful curve ever revealing something just on the horizon.


Free Puppet Opera ‘Mr. Twister and the Tale of Tornado Alley’ & Puppet-Making Workshop at Arboretum on June 10

The Arnold Arboretum is hosting a free operatic adventure with puppets about science and climate for children on Saturday, and there will also be a puppet-making workshop. The 45-minute performance of Mr. Twister and the Tale of Tornado Alley will be performed in the Bradley Rose Garden by the three ponds. Mr. Twister and the Tale of Tornado Alley follows Mr. Twister and his grandson Bobby on a journey around the globe—from the chilly arctic to the sizzlingly warm Gulf of Mexico. Through the power of his magic telescope, Mr. Twister can see just about everything—except the family reunion of the North and South winds that is about to create a cyclone in Tornado Alley! 
The performance begins promptly at noon, and attendees are being asked to please allow adequate time to find your way to the garden and get settled in for the show. Attendees are welcome to bring blankets or low chairs for the performance.


Hermaphrodite Conifer Cones at Arnold Arboretum — Are Not to Be Missed

Botany rule # 17: all conifer cones, for the last 300 million years (give or take) are unisexual. Each cone either produces pollen (male function through sperm) or seeds (female function through eggs). For well over a century, plant morphologists (members of a rarified discipline that focuses on the principles of plant form and was inaugurated by none other than Johann Wolfgang von Goethe) have known of conifer tree weirdos that can produce strange looking bisexual or hermaphrodite cones in addition to normal pollen-producing cones and seed-producing cones. While no one knows why this happens, it is rare and definitely something to see when the opportunity arises. [Week of April 29] at the Arboretum, one of our Lijiang spruces, Picea likiangensis (243-92*C) has broken bud, revealing hundreds of hermaphrodite cones right at eye level – and easily found at the south end of Conifer Path near Walter Street Gate.


Arnold Arboretum Welcomes Jessica Pederson as Head of Public Programs

The Arnold Arboretum of Harvard University recently announced that Jessica Pederson will be its new Head of Public Programs.

Pederson will lead a team of dedicated staff and volunteers to engage millions of Arboretum visitors both online and in person through creative events, programs, and public initiatives. As Head of Public Programs, Pederson will coordinate programming activities with partners in the city of Boston, Harvard University, and other civic and neighborhood organizations to advance the Arboretum’s commitment to equity and inclusion and promote its role as a community resource for education. Pederson marshals nearly two decades of experience in leadership at similar organizations including the Native Plant Trust, the Esplanade Association, and most recently the New England Botanic Garden at Tower Hill. She also previously worked at the Arnold Arboretum as a Hunnewell Summer Intern at the Dana Greenhouses and as Visitor Education Assistant. “I am thrilled to return to the Arnold Arboretum of Harvard University, where my love for public horticulture and environmental education first took root,” said Pederson.