This project collects observations of Erodium mericarps and seeds found in California. This is a subproject of
Erodium Genus (Stork's Bills) - California

The fruits of Erodiums are very similar in appearance and function: they coil when they dry out and uncoil when they get wet. The coiling/uncoiling action helps screw the seed (the arrowhead at the tip of the fruit) into the ground.

The following website has a short discussion of Erodiums species similarities and differences:
https://www.yosemitehikes.com/wildflowers/filaree/filaree.htm

Here's a paper that discusses the dispersal of Erodium seeds. It includes downloadable videos of the seed winding process:
https://journals.biologists.com/jeb/article/214/4/521/10703/The-mechanics-of-explosive-dispersal-and-self

References:

• Mericarp comparison chart for species of Erodium: https://idtools.org/id/weed-tool/key/GrapeSeedKey/Media/Html/fact_sheets/Erodium.html
• https://www.cabidigitallibrary.org/doi/10.1079/cabicompendium.114229
• Erodium moschatum seeds: https://idtools.org/id/weed-tool/key/GrapeSeedKey/Media/Html/fact_sheets/Ero-mos.html
• Eat the Weeds: Stork’s Bill, Cranesbill http://www.eattheweeds.com/erodium-circutarium-geranium-carolinianum-two-bills-you-want-to-get-2/
• https://www.google.com/search?client=safari&hl=en-us&sxsrf=APwXEdcJyfoy2zkKJeEFMBNo16U494Qenw:1685095929458&q=hairy+pitted+storks+bill+seed&tbm=isch&sa=X&ved=2ahUKEwiFpKbC35L_AhWtPEQIHXiyA9oQ0pQJegQIDBAB&biw=375&bih=550&dpr=2#imgrc=vQdY2Z3QceQI6M
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