Spreading seeds in the Riverwalk wetlands


By Josh Pike
Pagosa Wetland Partners

Fall plant activity in the Riverwalk wetlands is driven by the process of seed distribution. As plants die back or die off, they ensure that their physical structures maintain the integrity needed to produce seeds. At the same time, birds and mammals rummage through the wetland vegetation to locate the last fruits and hoard seeds for the winter. 

Photo courtesy Jeanette Pike
Other plants, such as the chokecherry, depend on animals to spread them by eating their seed-filled fruits. The birds and small mammals who eat these berries will digest their flesh and excrete the seeds, where they can then take root in the soil. This mechanism efficiently distributes seeds by rewarding animals with crucial nutrition in exchange for dispersing the plant’s seeds.

The seeds spreading through the wetlands are dispersed through several mechanisms, involving forces from wind to animals. In return, this distribution of seeds benefits the animals that spread them, with many being reliant on the fruits and seeds they gather for winter nutrition. Successful seed dispersal involves the plants, animals and weather of the wetlands working in concert toward a mutually beneficial end. Without all these players, the health of the wetlands would begin to falter as plants could not spread and the animals that rely on them would struggle. 

Photo courtesy Holly Matthews
Many plants, such as these cattails, distribute their seeds through the wind. The cattails produce large, tubular heads of seeds which are then frayed apart by wind and spread through the surrounding area, assisted by the white fuzz that surrounds each seed and enables it to glide through the air. Such plants typically produce large numbers of seeds to compensate for the many seeds that land in nonviable locations.

Thus, preserving the health of the wetlands requires protecting all its species and the integrity of the relationships between them. The photos and captions that accompany this story show some of the specific mechanisms plants use to distribute their seeds in the wetlands. 

If you want to learn more about the Riverwalk wetlands, you can contact the Pagosa Wetland Partners at pagosawetlands@gmail.com.

Photo courtesy Holly Matthews
Some plants use the fur and movements of animals to spread their seeds. Plants like American licorice produce seeds covered in burrs, designed to hook into the hides of passing animals and ride on them until they eventually drop off and potentially take root. Many of the burrs often found tangled in household pets are the products of this distribution method.