Arnold Arboretum of Harvard University

Starting Monday, March 31, Washington Street Gate and Blackwell Footpath in Bussey Brook Meadow will be temporarily closed to the public during the next phase of our Entrance Improvement Project. Over the next several months, the infrastructure and plantings at this entrance will be updated to increase accessibility and welcoming. The work is scheduled to be completed in October. In the meantime, we suggest that visitors follow directional signage in the landscape and use the Forest Hills entrance along the Arborway when going to or from the Forest Hills MBTA station. We appreciate your patience as we make these improvements!

Signs of Spring at the Arnold Arboretum: pussy willow, magnolia, maple, and witch-hazel flowers! #HarvardinSpring

"Hybrid witch hazels are amazing!" wrote Director Ned Friedman in his Post from the Collections newsletter this morning. "Crosses between the Chinese species of witch hazel (Hamamelis mollis) and the Japanese species of witch hazel (Hamamelis japonica) all began at the Arnold Arboretum in the 1920s and ultimately resulted in the all-star Hamamelis x intermedia ‘Arnold Promise.’ Horticulturists around the world have been repeating this cross ever since, and each time, something different results. At the Arnold Arboretum, you can see 12 (!) different Hamamelis x intermedia cultivars in flower right now. They range in color from yellow (like the Chinese species) to deep red (more akin to the Japanese species), with petals that can be curled and kinky to smooth and almost straight. Floral aromas go from faint to full on perfume shop. Since plants frequently lack reproductive barriers between related species, hybridization often leads to diverse horticultural outcomes that can surpass the characteristics of the parent plants. Pictured here are ten of the Hamamelis x intermedia cultivars at the Arnold. In order: ‘Arnold Promise’, ‘Barmstedt Gold’, ‘Angelly’, ‘Pallida’, ‘Jelena’, ‘Feuerzauber’, ‘Ruby Glow’, ‘Diane’, ‘Hiltingbury’, ‘Tsukuba no Kurenai’ (truly astonishing)." "What a great thing to reintroduce kissing cousin species from Japan and China to each other and let them make some magic. Whatever you do, get thee to the Arnold Arboretum ASAP. The witch hazels are at their peak."

"At the end of winter, seeds break their dormancy after several cycles of chilling and warming in the soil," writes Assistant Manager of Plant Production in a recent Arnoldia, "In a greenhouse environment, this occurs in stratification bags, where an average of 50 seeds are packed into a mix of moist sphagnum and sand. Seeds are stratified for anywhere from one to three months inside a walk-in cooler at 40*F. Particularly tough seeds require stratification at both cold and room temperature. Next, they are sown, on schedule, in a warm and humid greenhouse. The fracturing of the seed coat allows the seed to swell with moisture, which stimulates physiological changes needed for germination. When conditions are just right, the radicle taps itself downward to provide both anchorage and an adequate water supply for the emerging seedling. At the same time, the first seed leaves—cotyledons—will expand and begin photosynthesis. The second set of leaves—true leaves—begin to embody the characteristics of the parent plants. When leaves and stems are mature enough, they are potted up and continue their journey through the plant production pipeline." Keep an eye out for young seedlings in our nursery this summer, and become an Arboretum member to enjoy quarterly issues of Arnoldia! #arnoldiamag

Curatorial staff are on the hunt for emerging leaves! Currants and gooseberries (Ribes) are some of the first deciduous shrubs at the Arboretum to unfold their 3-5 lobed leaves. Although we’ve known by clock and calendar spring is on the move, our plants and their leaf out confirm it, too. Pictured: Chinese Winterberry Currant (Ribies fasciculatum var. chinense 613-88*MASS)

Meet our Members! In the spirit of collective action, the Arnold Arboretum Committee (AAC) was formed 40 years ago by a passionate group of advocates to help address security issues in the Arboretum. Founding members Ginnie and Keith Marcotte, along with others, raised funds in support of a park ranger program to enhance Arboretum visitor safety and enjoyment. Over the years, the AAC’s philanthropy has evolved to champion environmental sustainability in our landscape, funding green technology and equipment such as an electric loader, infrastructure for green waste renewal, and cargo bikes for our horticulturists. Their support has significantly improved how our staff does its work and how visitors experience the Arboretum and its collections. The Arboretum depends on the participation of its members, both individually and collectively, who help keep the Arnold Arboretum growing, thriving, and inviting to all.

This January and February, Bennington College students Jay Clark and Jester Wren spent their Field Work Term processing over two thousand documents and slide film comprising the North America-China Plant Exploration Consortium (NACPEC) archives. Their efforts mark the beginning of a project to compile, process, and publish the NACPEC and other modern expedition archives to increase their accessibility to researchers and the public. Featured here, we have a look into the Reading Room and a view of photographs (in protective mylar sleeves), a map, and the trip report for the 1994 NACPEC expedition to the Wudang mountains in Hubei Province, China.

Looking for some winter wonders on your snowy visit to our landscape? Here are some suggestions from our visitor engagement team: ?? stewartia ?? witch-hazel ?? conifer collection ?? winter hazel ?? maple collection

Introducing our newest pest control team at the Dana Greenhouses! We've incorporated some carnivorous plants (Pinguicula) into our integrated pest management program in the greenhouses. They are in peak bloom and hard at work—covered in fungus gnats and shore flies. We have them working in conjunction with classic sticky traps—a mixed approach that is a great fit for our smaller greenhouse and diverse plant mix. Native to Central and South America, the Pinguicula are epiphytic plants, thriving on moist bark and moss. They develop multiple rosettes of leaves that are easy to divide to create additional plants. They secrete digestive juices along their stems and leaves to trap and digest insects. And the best part? While our sticky traps sometimes snag beneficial critters like jumping spiders, these Pinguicula seem to only catch the pests!

Same deal as last weekend! Due to winter conditions, the Visitor Center is closed today, Sunday, 2/16. Stay safe!