#bryology

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Common apple moss is an adorable species of Bartramia that forms these little apple-shaped sporophytes. Each capsule has a cap with a tiny beak, giving the illusion of a stem. B. pomiformis grows all over the world, mostly on dirt, rocks, and felled tree trunks on humid forest floors.

This moss has lanceolate (lance-shaped) leaves, which curl when dry and straighten out when wet. They also form particularly long seta (sporophyte stems) compared to other similar species.

If you compare the leaf lengths of different species of mosses, you might notice that mosses which live under the cover of trees grow longer than mosses without a forest's protection. This is because moss's whole schtick is water retention, and if your leaves are long enough to be rustled around by the wind, you're going to lose a lot of water. Trees catch the wind in their leaves and slow it down, which allows mosses in forests to grow longer without losing precious moisture. This is also the reason that sporophyte capsules often grow much taller than the moss leaves - so the spores can catch the wind!