Spring Ephemerals – Dependent on Ants?
Found throughout the eastern United States and Canada, spring ephemerals thrive on the floor of rich, undisturbed woodlands and can be quite beautiful. This verdant, moist environment is the ideal site for myrmecochory, seed dispersal by ants. The seeds of spring ephemerals bear fatty external appendages called eliaosomes. The insects, attracted to the elaiosomes, carry the booty back to their nests, where the lipid-rich food source is consumed by their young. The unharmed seeds are thrown into a midden, a rich, composting stew that stimulates germination. A single ant colony may collect as many as a thousand seeds over a season. While the volume is great, the distance is not; on average, a seed is carried just two meters from the parent plant. Because offspring remain so local (unlike plants dispersed by birds or wind), habitat fragmentation is a major threat to the survival of spring ephemerals. Once these plants are gone from the forest, it is rare that they return. To help you identify these plants and their characteristics, view AllStar’s primer below.