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Sowing spores and culturing gametophytes is one of the major means of propagating ferns. Every year fern enthusiasts collect and mail spores to the AFS Spore Exchange. The Exchange is glad to get identified spores, in any condition, however, if possible it is better for everyone if the spores are properly cleaned. Contamination by fungi or bacteria is more likely when the spores are not separated from the chaff. The extra chaff also makes it difficult to estimate the number of spores sown. Following are instructions for cleaning spores to minimize these problems. 1. Place two pieces of clean white paper inside a clean single fold of newspaper. Position the spore-bearing frond, spore side down, between the white papers. If the frond is attached to a large rhizome (root), leave the rhizome outside of the paper (or remove it if you have no use for it). Place the newspaper between two pieces of cardboard and put a hard sided book on the upper cardboard. The cardboard flattens the frond and allows air to reach the frond. The specimen must not be pressed so tightly that moisture cannot escape resulting in sporangia that will not open. 2. Keep the specimen at room temperature in a dry place. A few days later (depending on humidity), most of the spores will have been released from their sporangia and will be lying on the white paper. If necessary, additional spores may be obtained by lightly brushing the frond with a small watercolor paintbrush. The spores will usually be mixed with chaff. The spores, distinguished with the naked eye, are tiny and colored yellow, brown, or black, whereas chaff is much larger and is usually a lighter brown than spores. 3. With one hand holding and slightly tilting the paper, take a pen with the other hand and tap lightly on the backside of the paper. The fiber of the paper holds the spores allowing the chaff to run down the paper faster than the spores. Discard the chaff. 4. With vigorous tapping, the spores can be dislocated from the white paper onto a smaller piece of clean paper that can be folded into a packet and mailed to the exchange. Fold this paper in a boat like fashion so that there are no places for spores to leak out. Place the folded packet into a regular envelope to mail to the curator. (Do not put the spores directly into a regular envelope; the spores stick to most envelops.) Glassine envelopes (like those used by stamp collectors) are ideal for spore packets, though be sure to tape the seams to keep spores from leaking out. 5. Label the packet with the species name, where it was collected, and any other relevant information. Species information that is helpful is size, common name, habitat, and the hardiness zone where the fern was growing.
6. Mail the spores to:
Denia Mandt, |