On the move: How plants disperse seeds

 The ants go marching one by one, but what are they carrying? 

Ants can disperse seeds by carrying them as they walk. (Photo via Shutterstock)

Plants are clever in many ways! One of the most impressive and diverse adaptations is how they spread their seeds.

From maple trees' whirligig seeds flying on the wind to cocklebur seeds that stick to animal fur (and even your pant leg), there are many dispersal methods plants use. Let’s check out one example that is often overlooked. 

Trash and treasure 

Seeds in a pod covered by a substance called an elaiosome. (Photo via Shutterstock)

In the spring, flowers like trilliums, bloodroot and Dutchman's breeches have seeds covered in a yummy substance called an elaiosome (pronounced "uh-LIGH-uh-sohm"). The elaiosome looks like a small cap or mohawk on the seed and is full of protein that nourishes growing ant larvae. 

It’s sort of like eating a banana then composting the peel: An ant will take the elaiosome-covered wildflower seed to their nest to feed their larvae and toss the seed into an area designated for waste disposal. Using nutrients from the ant colony's leftovers, the wildflower seedling can grow. 

This dispersal method is called myrmecochory (pronounced "mur-mi-koh-KOR-ee"). It is one example of how plants and animals work in harmony. The flower's seed gets planted in a nutrient-rich spot and the ants get a delicious treat! This is one of many mutualistic relationships in the wild. Can you think of any other ways animals or plants work together? 

Why do seeds travel? 

Dandelion seeds carry on the wind. (Photo via Shutterstock)

There are many ways for a plant to move its seeds from one place to another, but why is this important? Like humans, plants need food, water and space to survive. Plants do not like competition. If there aren’t enough nutrients in its area, a plant isn't able to walk to a new space with all the resources it needs. Instead, the mothering plant will disperse its seeds far away from itself in hopes a seed will land in a spot where the baby plant doesn't have to struggle for resources. 

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Words to know 

Disperse: Spread in different directions. 

Elaiosome: Nutrient-rich attachment on certain plant seeds that attract ants.

Larvae: Newly hatched form of an insect.

Mutualism: A relationship that benefits both individuals.

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Another limited resource plants need to grow is sunlight. Imagine a giant oak tree with thousands of leaves. Below this tree will be a lot of shade. If the mother oak tree drops its seeds right underneath itself, the baby sapling won't get the sunlight it needs.

Just like the elaiosome of some wildflower seeds, oak tree seeds taste great to certain animals. These seeds (we call them acorns) are taken by squirrels to other locations. When a squirrel forgets where it buried its mid-winter snack, the acorn can grow in a new spot and not compete for resources with its mother tree. 

Where to see mutualism in action

A trillium plant at Raccoon Grove Nature Preserve. (Photo by Glenn P. Knoblock)

Will County has many sites to see wildflowers that use special seed dispersal methods! Raccoon Grove Nature Preserve in Monee includes a short, 0.27-mile trail that fills up with spring wildflowers between April and June. It is a prime spot to find trillium. Looking for Dutchman's breeches? Head over to Hidden Oaks Preserve in Bolingbrook from April to early May. Another top spot is O'Hara Woods Preserve in Romeoville, where wildflower viewing is impressive from April to June!