Glossary

elaiosome

Elaiosome (ee-lay-ó-sohm) is a fleshy, oil-rich structure attached to certain seeds that attracts ants. Ants carry these seeds back to their nests, eat the elaiosomes, and discard the still-viable seeds in loosened soil near the nest entrance, conditions that favor germination.

This process, known as myrmecochory, aids in seed dispersal and helps some native plants establish in shaded forest floors or undisturbed soils.

In the Santa Cruz Mountains, Western Trillium (Trillium ovatum) is a confirmed example — its seeds carry elaiosomes that attract native ants, which disperse them through the forest understory.

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