Having fun with Mesembryanthemum fruit capsules
The fruit capsules
If you have ever tried to extract seeds from a dried fruit capsule of a member of the Mesembryanthemum family, you will in all likelihood have suffered a couple of broken nails and a fair amount of frustration. Mother Nature shows us how it's done....
Most members of the Mesembryanthemum family have disc-shaped fruit capsules with cavities or chambers in which the tiny seeds are held and which are closed with various membranes and valves, which differ according to the various species.
Hygrochastic seed dispersal
The capsules ripen and dry out on the plant but remain tightly closed until it rains, when the valves open to allow some seed to be dispersed by the falling raindrops. As the capsules dry they close up again and re-open with the next rain, once again allowing a few seeds to escape. This results in a greater possibility of suitable conditions for germination. The term used for this method of seed dispersal is hygrochastic.
When I first heard about this I thought it was a bit far-fetched and just had to try it out. It is truly fascinating. You spray the dried capsules so that they are quite wet. In a very short time the valves open, exposing the seeds. The capsule then closes as it dries out.
The capsules are extremely tough and this is a magical way to get to the seeds without breaking your nails or resorting to pliers.
Please forgive the poor quality of the photos - I'll do them again sometime, but for now this will have to do.