Every winter, teams of horticulture staff members scout a random assortment of our susceptible trees for the presence of the invasive Asian long-horned beetle (Anoplophora glabripennis). Maples, elms, willows, horse chestnuts, and poplars are some of their preferred hosts. We record the DBH of the tree, note the start time, and scan the trunk and each branch of a selected tree with binoculars, which is much easier when the trees are lacking foliage. We’re looking for any egg-laying sites chewed into the bark by the females, or exit holes from emerging adults after tunneling and feeding on the tree’s sapwood and heartwood. A single tree, tall enough and with a spreading crown, could take a group of three over an hour to scout, or a cumulative three work hours to check that specimen. Luckily, ALB has not been detected in the Arboretum. For the health and safety of our collections, we will continue to be vigilant in our yearly scour of the landscape for this destructive pest.


Accessions on the susceptible tree list.


Trees surveyed per winter.

Rachel Lawlor is a horticulturist at the Arnold Arboretum.

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.