Meg Engelhardt is Missouri Botanical Garden’s Seed Bank Manager. She describes her ex situ conservation program and its applications for ecological restoration.
Seeds have been stored for food since the dawn of agriculture, but in recent decades seed banks have become an increasingly relied upon tool for plant conservation. Ideally we would conserve all plants in their natural habitats, or in situ. After all, when plant populations remain intact so do the relationships with other organisms in their ecosystems. Intact plant populations also maintain gene flow within the species, helping populations continually adapt to their surrounding environments. Unfortunately, it is not always possible to maintain wild plant populations. Even when resources are available, maintaining natural plant populations may be impossible due to habitat fragmentation or destruction, range shifts due to climate change, pollinator loss, or any list of known or unknown factors resulting in population decline. This is where seed banking, or ex situ conservation, may play a supporting role.
Collecting seeds from a dolomite glade in Franklin County, Missouri
Seed banks are long term storage facilities designed to keep seed viable for years and even decades. Those seeds can then be used for research, restoration, reintroduction, or education.
Maybe you have heard of the Svalbard “doomsday” Seed Vault, where seeds of more than 4000 plant species are stored deep below the permafrost near the north pole. Or perhaps the Millennium Seed Bank, which holds 13% of the world’s wild plant species and continues to collect the world’s threatened flora. Here in the United States we have the Native Plant Germplasm System, a network of 20 storage facilities across the country that store over 15,000 species, with a focus on agriculturally important species. On a more local scale, many small seed banks are used to conserve regionally important, threatened species.
Inside a very large freezer at the National Center for Genetic Resources Preservation in Ft. Collins, Colorado
The Missouri Botanical Garden has been seed banking for over thirty years. In 1984 the Center for Plant Conservation (CPC) was founded with Missouri Botanical Garden as a founding member. CPC is a network of 40 botanical institutions focused on ex situ conservation of rare plant material while also ensuring material is available for restoration and recovery efforts. Our CPC collection is currently maintained by staff who are actively seed banking, researching, and restoring populations of extremely rare native plants throughout southeastern US (Solidago ouachitensis, for example).
Additionally, seed collecting and short term seed storage has been going on for at least 25 years at Missouri Botanical Garden’s Shaw Nature Reserve. Horticulture staff at the Reserve are focused on local ecotype native plant horticulture and have been collecting seed from regional wild sources for use in small scale greenhouse propagation, use in the Whitmire Wildflower Garden, restoration projects throughout the Reserve, and various other partnerships that encourage native plant horticulture.
The Shaw Nature Reserve “seed closet” currently houses almost 500 different taxa ‒ most of which are local wild source (i.e., seed collected from plants growing in the wild) or second generation seeds (i.e., the first descendants of plants growing in the wild).
In 2013 the Missouri Botanical Garden Seed Bank was created with two main goals. First to advance seed banking at an institutional level by providing support and facilities. A new seed lab space was created at Shaw Nature Reserve which includes lab benches and space for processing collected seed and cleaning for storage as well as a refrigerator and freezer storage space. The second goal is to collect and store samples of Missouri’s entire flora, which includes roughly 2,055 taxa. Continually collecting and storing samples of all local species will ensure long term genetic conservation that can be made available for research, restoration, and recovery should the need arise.
Missouri Evening Primrose, Oenothera macrocarpa
Natural History of Ecological Restoration 