9. TARGETING THE POPULATION(S) FOR COLLECTION

It is essential that a knowledgeable botanist familiar with the target species leads the collection and is involved in identifying the most suitable population(s) for sampling.  Choosing target populations will be up to the lead botanists and plant ecologists working at the field office level in BLM and at other collecting partner institutions.  An “ideal” collection will be from a large number of individuals (between 100 and 500) and will contain more than 10,000 viable seeds.  Collections larger than 20,000 viable seeds are preferred; collections this large maximize the flexibility of the collection and allow for a portion of the collection be held at a second seed bank.  Maximizing the use of the collection means that:

• Sufficient seed is available for germination and viability testing
• Samples are available for distribution to users for restoration, education or scientific purposes
• A substantial amount of seed can be conserved as a long term safeguard against loss of the wild population

Where populations are suitable and the quality and quantity of seed is adequate, it may be possible to make collections of a number of different species from the same site.  Preliminary site visits are often necessary to assess the populations, confirm the identification with the collection of herbarium voucher specimens (see Section 11), and estimate the likely harvesting date and potential seed production.

The following points should be considered before harvesting takes place:

• Ensure that the population is of wild origin, not planted or cultivated.  For example, do not collect seeds of native species that were included in a seed mix as part of post fire management in areas that were burned and seeded.  Native species that were not seeded in those areas could be collected.
• Small populations (less than 50 individuals) or those that will yield less than 1,000 viable seeds in a collection following the sampling strategy above should not be collected.  Seed development can vary within and between populations of the same species.  Monitor seed maturation and to assess insect damage and empty seeds throughout the population before making the seed collection.
• Collections taken from the exact same population may be combined in to one accession (seed collection reference number) over the course of a season to maximize genetic diversity and collection material.  Collectors must ensure that no more than 20% of the viable seeds are collected on any given day, and that all combined material is from the same population and uses the same seed collection reference number or accession number.  Note on the SOS field data form the dates the material was collected.