What Is an Elaiosome? Seed Appendages That Ants Carry Off
An elaiosome is a small food body of fats and sugars attached to the coat of some seeds. The Illinois Department of Natural Resources says ants carry these seeds home, eat the elaiosome and leave the seed unharmed. The seed then sprouts somewhere new.
The short answer
An elaiosome is a fatty snack attached to a seed. Ants haul the seed to their nest, eat the elaiosome and discard the seed in nutrient rich waste piles, as Illinois DNR describes. The plant gets its seed moved and sown. Bloodroot, trilliums, violets and wild ginger use this trick.
How does ant seed dispersal work?
Botanists call it myrmecochory. The Xerces Society says over 11,000 plant species rely on ants this way. Ants carry the seed into the nest, feed the elaiosome to their larvae and toss it out. Illinois DNR notes the seed often lands in a nutrient rich waste pile, a good place to germinate.
| Plant | Disperser | Source |
|---|---|---|
| Bloodroot | Ants | NC State, Illinois DNR |
| Trillium | Ants and yellow jackets | NC State |
| Violets | Ants | Illinois DNR |
| Wild ginger | Ants | Illinois DNR |
| Dutchman’s breeches | Ants | Illinois DNR |
Where can I see an elaiosome?
Look at bloodroot or trillium seed in late spring. NC State notes ants eat and spread bloodroot seed. The elaiosome is a pale fleshy lump on one side of the darker seed. Set a few seeds near an ant trail and watch them vanish.
Why does it matter for gardeners?
Ant dispersed plants spread slowly and patchily. NC State says trillium may take seven or more years from seed to bloom. Each step of that slow life cycle of a marijuana plant begins with an ant trip.
Elaiosomes and other insects
Ants aren’t the only insects that move plant parts. Bees move pollen between flowers, as what roles do bees play in outdoor cannabis explains. The Kind Seed Co blog covers mixed plantings in companion plants when growing marijuana. For the basic layout of a seed under the elaiosome, see cannabis seed anatomy.
Sources
- Flowers and ants, Illinois Department of Natural Resources
- Myrmecochory: how ants shape plant communities, Xerces Society
- Sanguinaria canadensis (bloodroot), NC State Extension Gardener Plant Toolbox
- Trillium, NC State Extension Gardener Plant Toolbox
FAQ
What is an elaiosome made of?
Illinois DNR describes it as a structure of fats and sugars attached to the seed coat.
Do ants eat the seed?
No. Illinois DNR says ants eat the elaiosome and leave the seed unharmed.
How many plants use ants to spread seeds?
The Xerces Society says over 11,000 plant species use ants for seed dispersal.
Which garden plants have elaiosomes?
Illinois DNR lists bloodroot, Dutchman's breeches, trilliums, violets and wild ginger.
How long does trillium take to bloom from seed?
NC State says it may take seven or more years from seed to bloom.
