Growing Moss, Science and Conservation with Seniors


Growing Moss, Science and Conservation with Seniors

By: Lalita Calabria, visiting faculty, The Evergreen State College, Washington; Shana Gross, ecologist, Lake Tahoe Basin Management Unit, US Forest Service; and Nalini Nadkarni, forest ecologist and science communcator, Department of Biology, University of Utah

Publish Date: April  04,  2014

Senior citizens are often overlooked in terms of both science education and citizen science-type collaborations with scientists. We engaged senior citizens and students to help address a pressing environmental issue – the non-sustainable harvesting of ecologically important moss from old growth forests for the floriculture trade. Few protocols exist to cultivate large quantities of mosses despite concern of negative effects of widespread moss harvest in the Pacific Northwest.  Our goal was to develop techniques to “farm” mosses by examining  effects of species and substrate on moss growth rates. Measurements of moss growth were recorded weekly by a team of seniors and college students for three months. Inclusion of senior citizens, a public group that has rarely been included in citizen science efforts, was productive.


seniors-and-moss.gifScientists are increasingly engaging the general public to help with gathering data for their research programs, a practice known as “citizen science”. This includes such projects as tracking the seasonality of backyard plants to monitor climate change, and accounting for the number of bird species in an area in “Christmas bird counts”. There is a tendancy for scientists to include young to middle-aged, physically active, and environmentally aware participants. However, seniors are a potentially rich source of scientific collaboration because they tend to value activities that keep their minds and bodies active and challenged. Most are retired, and have time during weekdays to contribute to projects. Many can draw upon skills and experience garnered during their professional lives. In 2010, we partnered with the Research Ambassador Program ( ), a community senior center, and the Evergreen State College (TESC) to develop methods of growing moss that might help offset the demands of a growing environmental problem, the unsustainable harvesting of mosses from old-growth forests of the Pacific Northwest.  Scientists and seniors together developed protocols that might relieve pressure from the practice of wild-harvesting mosses for the floral industry in the Pacific Northwest. Moss harvested from these forests is in increasing demand for commercial use in decorating plant pots, packing bulbs for transport, moss bags, and other home decorative uses. The Pacific Northwest supports one of the greatest diversity of mosses in the world and produced at least 22 million pounds of commercially sold forest moss in 1999 alone. Currently, commercial moss harvest is an international, multimillion-dollar industry.


Although moss harvesting is a relatively minor threat to moss communities in comparison to land development and mining pressures, there is growing concern that the harvest of large amounts of forest moss may have negative impacts on ecosystem functions. In particular, their importance in water and nutrient cycles and enhancement of animal habitats makes their removal problematic. Further, the slow rate of documented regrowth in some regions, which can be as long as 20-30 years in the Pacific Northwest indicates these impacts can have long term effects on moss communities, species richness and overall ecosystem health.


seniors-and-moss2.gifProtocols do not currently exist for cultivating mosses in large quantities, and the existing literature focuses mainly on growing small quantities for home gardening or greenhouse propagation of moss. Recently, botanists have tried to develop methods to grow mosses on a larger scale in prisons, for restoration of roadsides in the Lake Tahoe region of California, and for trailsides in national parks. However, these efforts have been preliminary and specific to particular species of mosses. Our goal was to determine basic aspects of moss horticulture, particularly which species of moss and which types of substrates would promote the most rapid moss growth.


We built an active partnership with Senior Services of South Sound at the Olympia Senior Center, drawing upon their pool of seniors, communication network, classroom space for the workshop, staff assistance, and growing space for the three month period of our study.  Our first event was a lecture and workshop that introduced the seniors to the basic characteristics and biology of mosses, their roles in ecosystems, and the negative impacts of the horticulture industry on forest mosses. Seniors also learned to recognize differences among moss species with dissecting microscopes. A subset of these participants assisted in the development of a research experiment, with six undergraduate students from the Evergreen State College. The students contributed to data collection and logistics, and helped create a deeper scientific and inter-generational dialogue. The team of students, scientists, and seniors collectively developed an experimental plan to learn which species grows faster and on which substrate type.


Having our moss growth experiment located in the main lobby of the Senior Center generated public attention. We posted signs to explain the experiment and basic ecology of mosses inside and outside the Senior Center.  We conducted our weekly measurement sessions at a table in a high traffic area, which allowed passers-by to stop and ask questions. The local newspaper (The Olympian) wrote a piece about the project highlighting the positive connection we created between academia and the public.

Seniors proved to be an excellent source of help and scientific insight throughout the length of the project. The students functioned as the "glue" among all of the participants. Seniors discussed the project and its values for them with their families and other seniors during and after the project.

Although science may be perceived as neat, clean, and organized, the ‘practice’ of science represents iterations of trials, errors, and often, accidental discoveries. By encouraging seniors’ input as we developed the experimental design and methods, this non-scientific audience witnessed the evolution of a real scientific project.

Seniors represent an audience that is accessible to nearly every academic scientist. There are analogues to the Senior Services for South Sound in nearly every community in the country. This part of our society – though in some cases not as mobile or vocal as participants in typical citizen scientist project, were receptive, responsible, interested in nature and learning, and can themselves become conduits of scientific information.

Acknowledgments: We thank the Evergreen State College and The Olympia Senior Center for their support in conducting this research and the dedicated staff who coordinated all research activities, Amy Stasch, Sara Rucker Thiessen and Chris Quimby. We are especially greatful to the seniors and students who helped design and conduct the moss propogation experiment, Tamara Cowles, Caitlin Fate, Shay Hohmann Margaret Krug, Bobbie Moody, Paul Moody and Dorothy Wilson. This research was supported by an EAGER Ecosystems Program grant from the National Science Foundation (DEB 11- 41833


About the authors

Lalita Calabria ( ) is a visiting faculty at the Evergreen State College, Washington where she teaches plant biology, taxonomy and field ecology. She studies florisitics, taxonomy and conservation biology of bryophytes and lichens in temperate North America.


Shana Gross is an ecologist for the Lake Tahoe Basin Management Unit, US Forest Service. She studies ecosystem management and helps translate science to natural resource professionals and the community. During her graduate work she studied propagation of bryophytes for use in roadside restoration.


Nalini Nadkarni is a forest ecologist and science communicator at the University of Utah. She studies canopy biology in temperate and tropical rainforests. She carries out science outreach to a variety of underserved public audiences around the country