Growing a Museum Specimen

Two Arboretum collectors—Tiffany Enzenbacher and Kea Woodruff—spent nine days travelling in and near the Ozark Mountains of Arkansas. Enzenbacher is the manager of plant production at the Arboretum’s Dana Greenhouses, and Woodruff was then the plant growth facilities manager at the Arboretum’s Weld Hill Research Building.

The Ozark Mountains region is known for harboring some of the most biodiverse oak-hickory forests in the country.

At the Blue River, Enzenbacher and Woodruff were accompanied by Matt Gamble and Ethan Lovelace of the Oklahoma Department of Wildlife Conservation.

The collectors found seaside alder bearing seeds. Although the seed-bearing catkins were still green, the seed inside was ripe.

Seaside alder tolerates exceptionally wet conditions. At the Blue River, some of the alders were partially submerged in flowing water.

In addition to obtaining seed of the alder, the collectors also recorded detailed information about the plants and their native habitat. These hand-written notes would later be entered into the Arboretum’s plant-records database. These records are especially important for research and conservation purposes.

The collectors also prepared an herbarium specimen of the seaside alder. This dried sample provides essential documentation of the parent plants and will be referenced by researchers for centuries to come.

Seeds of the seaside alder were shipped via FedEx back to the Arnold Arboretum’s Dana Greenhouses, which Enzenbacher manages.

Oil-rich seeds like acorns are shipped in cloth bags, while smaller seeds, like those of the alder, are shipped in plastic.

At the Dana Greenhouses, staff sorted and counted seeds from the expedition. Here propagator Sean Halloran sorts seeds of the seaside alder.

For germination to occur, the seeds of some plant species require refrigeration, which mimics a winter cold period. Others require treatments that soften or weaken the outside of the seed. Every plant is different, and Arboretum staff have documented their propagation experiments for almost 150 years.

Halloran referenced these extensive propagation records, which indicated the seaside alder would germinate easily. The seeds could be sown and placed directly into the greenhouse.

The following spring, seedlings of seaside alder were moved from the greenhouse and transplanted into a shade-covered seedling nursery. Chris Copeland, the greenhouse horticultural technologist, works with other greenhouse staff and interns to care for the plants.

The seaside alders will later be transplanted into the primary outdoor nursery. After two to four years, Arboretum staff will determine which specimens of seaside alder are performing best in the nursery and which should be planted on the Arboretum grounds.