Method

Rationale

1.

Assess the target population and confirm that a sufficient number of individual plants (> 50) have seeds at natural dispersal stage.

To ensure that adequate genetic diversity can be sampled from the population, and that the seeds are likely to be at maximum possible viability and longevity.

2.

Carefully examine a small, representative sample of seeds using a cut test and for smaller seeds a hand lens.

Estimate the frequency of empty or damaged seeds and confirm that the majority of seeds are mature and fully formed.

3.

Collect mature, dry seeds into either cloth or brown paper bags.  Large collections can be made using plastic buckets and then transferred into bags.

Ensure the highest possible viability at collection and maximize the potential storage life.

4.

In general, cleaning should be left to the processing staff at the MSB and Bend Seed Extractory. 

Maximize the use of available field time and clean and prepare seeds in controlled laboratory conditions.

5.

Fleshy fruits should be collected directly into plastic bags. Specific advice on ripening and cleaning fleshy fruits is in Section 15, or contact RBG, Kew or Bend Staff if specific guidance is needed.

Fleshy fruits decompose rapidly and poor storage can lead to mold infested seed collections.

6.

Sample equally and randomly across the extent of the population, maintaining a record of the number of individuals sampled.

Capture the widest possible genetic diversity from the plant population sampled.  Where the population exhibits a pattern of local variation, use a stratified random sampling method to ensure sampling from each microsite.

7.

Collect no more than 20% of the viable seed available on the day of collection.

Ensure that the sampled population is not over collected and is maintainable.

8.

Collect seeds from a population throughout its dispersal season, seeds from a population collected in the same year can be combined as one collection, using the same seed collection reference number.  Note the multiple dates of collections on the SOS field data form.

Maximize genetic diversity in the collection, capturing early, mid, and late bloomers.

9.

Collect 10,000 to 20,000 viable seeds.

Enable maximum use and study of the collection.

10.

Collections of all sizes are welcome, at both MSB and Bend.  However, the smaller the collection, the less use will be made of it.

Less use will be made of these collections.

11.

Collections > 20,000 are most desirable.  Collections sent to the MSB are halved upon return to the U.S., and as quantities allow, will be made available for distribution.

This ensures long-term storage at 2 facilities, and a working collection that can be made available for researchers.  Halved MSB collections will be stored for long-term conservation, but will probably not be available for distribution.

12.

Collections sent to Bend can be cleaned and sent back to collectors if they are needed for native plant materials development research or a re-seeding project.  The first 10,000 seeds of each collection sent to Bend becomes part of the SOS National Collection. See Section 17 for details on requesting material from Bend.

Seeds 1-2,500: Long-term Storage at NCGRP, Ft. Collins, CO
Seeds 2,501-5,000 – Long-term Storage at Western Regional Plant Introduction Station, Pullman, WA
Seeds 5,001 to 10,000 – Working Collection, available for distribution through the Germplasm Resource Information Network

13.

Collections between 1,000 and 5,000 viable seeds are welcome, but distribution opportunities are limited.

Less use will be made of these collections.

14.

Collections of less than 1,000 seeds are welcome at RBG, Kew only when more productive populations are not available for sampling.

These samples will not receive any testing at RBG, Kew and if sent to Bend will not be available for distribution.

15.

For each collection, estimate the viable seed production per fruit, per individual and per population, and note these on the field data form.

Document species seed biology, better assess the influence of collecting on the population, and gather information to better document if we are meeting Standards for Rangeland Health for native plant communities.

16.

Clearly label all bags (inside and out) with the appropriate collection number.  No other data needs to be included on the label.  Do not write on the cotton seed bags with permanent marker because it hinders their re-use in the seed collection program.

To ensure that this unique identifier is attached to each sample of a collection.  All other data will be recorded on the field data form.