Collecting Spores for the AFS Exchange

The Spore Exchange welcomes spore donations from members and non-members.  Any fern species or variant is much appreciated.  Of course, donations that add new species or update existing species are preferred but any contribution will be accepted.  Please try to collect enough spores to make three or more packets (approximately 15 cubic millimeters of cleaned spores, minimum).  The other extreme, very large spore quantities, might fill research needs or allow possible trading with other fern societies.

A PDF presentation on collecting spores is available here. Or, read below for instructions on spore collecting.

If you think a fern is too common or ordinary to donate, it might be just what a beginner, researcher, or someone in another area is looking for.

Following these guidelines will help avoid some common problems with donated spores such as unripe or over-ripe spores, contamination, incorrect identification, and leaking of spores in transit.  For an in-depth treatment on spore collecting, download How To Collect Fern Spores, an excellent Powerpoint presentation by the late Barbara Joe Hoshizaki.

1.  If possible, take some digital photographs of the fern you are collecting spores from.  Try to include an ordinary object in at least one picture for size reference.  Links to donor-supplied pictures will be included in the online list.  If you do not know the botanical name of the fern or if you are unsure, please send pictures of the plant, both sides of the fronds and close-ups of the fertile fronds.  Sending portions of the dried fronds is also helpful.  The pictures and/or fronds should allow identification to the genus level for listing on the exchange.

2. Collect fertile fronds or portions of fertile fronds with ripe sori (spore bearing patches).  Ripe sori contain sporangia (tiny capsules) that are fully developed but have not yet released their spores.  Unripe sori are generally green or somewhat colorless while over-ripe sori have spent sporangia which look like dull fuzz.  If in doubt, collect portions at various stages of development.  Also, it is better to error toward over-ripe fronds than under-ripe ones because good spores are more likely found among spent sporangia than among unripe sporangia.


3. If the source fern is in a location where it may have received wind-blown spores from other species, or if its fronds are dirty, then thoroughly rinse the cut fronds in a strong stream of cool water and shake off the excess.

4. Place the collected fronds in a thin white paper envelope - a business envelope will do - and allow it to dry at room temperature for a few days.  Another method is to sandwich the fronds between sheets of white paper held down with a weight.  You can reduce the drying time to a few hours by scraping the sori off the frond into the envelope or onto a sheet of paper, making sure the scrapings are spread out.  Since the spores are thrown one or two inches from the sporangia during the drying process, close the envelope or provide baffles to contain the spores.

5. After the fronds have shriveled and the sporangia have shed their spores, there will be a dusty mixture of spores and chaff (spent sporangia, dried indusia, scales, etc.).  Brush off or tap any remaining material from the fronds before discarding.  Remove most of the chaff from the spores by holding the paper at a slight angle and tapping it so that the chaff bounces forward while the spores stay behind.  Don't worry if some chaff remains.  If your attempt to clean the spores does not work or you are unsure if there are any spores, go ahead and send all the released or scraped material. All donations will be cleaned using a fine metal sieve when processed for the spore bank.

6.Seal the spores of each donation in a folded paper packet.  There are many packet folding methods but the trick to successful sealing is making a packet where the only route of escape is a sequence of at least two very sharp folds.  Also, the packet needs to lay flat, otherwise the trapped air inside will blow the spores out if it is squeezed.  Ideally, the paper should be thin, smooth, and white, or translucent.  Heavy duty aluminum foil also works well but waxed paper has been shown to decrease spore longevity.  Please do not put the spores directly in a plastic bag and do not use tape to provide a seal.  Spores and chaff tend to statically cling to plastic and adhere en masse to tape residue.  Instead, consider enclosing each folded packet in a small sealed bag.  It will hold the packet from unfolding and contain any mess if it leaks.

7.Label each packet, or the bag containing the packet, with the botanical name, collection month and year, your initials, and a "g" if the fern was grown (cultivated) or a "w" if it was wild collected.  If collected in the wild, please also include the location (country, state, province, etc.).  Any additional information would be helpful such as habitat, elevation, soil type, hardiness zone, etc.

If the packets are thin, less than 1/8th inch thick, tape them to a sheet of paper using clear (preferably removable) tape, fold the paper and mail in an ordinary business envelope.  Otherwise, send the packets in bulk using a padded shipping envelope.

9.Mail spores to:

Brian Aikins
AFS Spore Exchange
3523 Federal Ave.
Everett, WA 98201-4647

10.Email pictures, or better yet, links to the pictures to  Please be sure to identify which pictures go with which packets.

Banner image (Cibotium glaucum) by Tom Ranker.