Conservation Seed Collection
The Santa Barbara Botanic Garden’s long-term Conservation Seed Collection currently represents over 160,000 seeds, composed of 404 accessions and 127 Species. These include state and federally listed species, Bureau of Land Management and US Forest Service sensitive species, and special collections of disjunct populations. Application to access these collections for authorized research, recovery, or reintroduction purposes can be made to the Conservation Program Manager, or call (805) 682-4726 ext. 128.
The Santa Barbara Botanic Garden Conservation Seed Collection:
Seeds are the structures by which plants reproduce new plants, maintaining continuity over generations and serving as units of dispersal that can generate new populations in suitable habitats. Products of pollination, seeds represent packages of genetic information encapsulated in dormant embryos, which can be used to generate new plants in the next growing season or stored for many decades under appropriate conditions. Consequently, seeds provide the most economical approach to restoring or augmenting established populations of plants or reintroducing them to suitable habitats.
Seed storage requires an understanding of the biology of individual species, and the kinds of seeds that they produce. Most seeds are classified either as “orthodox” or as “recalcitrant”. Orthodox seeds have a natural long-term dormancy provided for by intrinsic physiological or structural features. For example, most plants that regenerate from seeds following fire have orthodox seeds; their long-lived seeds are capable of germinating after periodic fire. Their dormancy may be broken through the effect of chemicals produced by smoke or by having their thick coats crack from heat. Other orthodox seeds are naturally programmed to germinate at slow intervals, thus contributing to overlapping generations of plants, as open sites become available for germination. Most desert species have orthodox seeds, which germinate only after exposure to at least one period (e.g., summer) of relatively high temperatures. Regardless of how dormancy is broken prior to germination, orthodox seeds are easily stored in seed banks. In contrast, recalcitrant seeds are those that usually have a naturally low life span and do not survive freezing temperatures. For example, the seeds of the oak family (Fagaceae) are generally recalcitrant, and may live only for a few years, even under standard storage conditions, which include relatively high humidity and low, but not freezing, temperatures. Species with recalcitrant seeds require special attention and different conservation strategies.
Successful implementation of conservation efforts often include multiple strategies, ranging from protection on public lands to reintroduction, recovery, and, in rare cases, rescue of plants for which no other conservation strategy is viable. Seeds play a crucial role in many of these efforts. Selection, collection, and preparation of seeds prior to storage in a seed bank are all critical factors in the scientific value of the accessions. Seed selection and collection requires special attention to ensure capturing the genetic diversity of a population. Seed preparation involves cleaning and controlled dehydration, prior to storage at -18° centigrade. Documentation, in the form of a database, records as much information as possible to assist management and use of the collection in future research and conservation activities. Seed banks provide an efficient method for storing large numbers of seeds over long periods of time; they are, effectively, an insurance policy against decline or loss of populations.