Plant propagation is both traditional art and applied science. Made from mature, dormant stems, hardwood cuttings are just one clonal propagation technique we use at the Arnold Arboretum to coax life from some of our most valuable accessions. In New England, we can root hemlock and many other genera via this technique. We collect hardwood material in late fall or early winter after plants enter dormancy and deciduous plants have lost their leaves, selecting younger, healthy stock for optimal results. Hormone is applied to the freshly prepared cuttings, which are usually “stuck” the same day they are collected, in benches filled with quick-draining growing media, tented with plastic to ensure high humidity, and heated from below to encourage rooting. Hormones and wounding treatments are taxon-specific, based upon the scientific literature as well as our own propagation records. Cuttings that survive and root will be potted up in the spring or early summer, eventually to serve as prized members of the next generation of our collections.


Number of cuttings collected per accession.


Accessions in the collections being actively propagated.

Sean Halloran was Plant Propagator at the Arnold Arboretum from 2016 to 2022.

From “free” to “friend”…

Established in 1911 as the Bulletin of Popular Information, Arnoldia has long been a definitive forum for conversations about temperate woody plants and their landscapes. In 2022, we rolled out a new vision for the magazine as a vigorous forum for tales of plant exploration, behind-the-scenes glimpses of botanical research, and deep dives into the history of gardens, landscapes, and science. The new Arnoldia includes poetry, visual art, and literary essays, following the human imagination wherever it entangles with trees.

It takes resources to gather and nurture these new voices, and we depend on the support of our member-subscribers to make it possible. But membership means more: by becoming a member of the Arnold Arboretum, you help to keep our collection vibrant and our research and educational mission active. Through the pages of Arnoldia, you can take part in the life of this free-to-all landscape whether you live next door or an ocean away.

For more tree-entangled art, science, and writing, subscribe to Arnoldia by becoming a member of the Arnold Arboretum.