Top Story: September 7, 2012

Citizen Science on Mt. Tam


By Jeroen Lapré

I had a great time at the Mt. Tam Plant Survey on Saturday, August 25! The event was coordinated by Alison Young, Citizen Science Educator here at the Academy, and Suzanne Whelan and Andrea Williams of the Marin Municipal Water District (MMWD). This day was part of the larger Mount Tamalpais plant survey citizen science project, a partnership between the Academy and the MMWD. According to Alison, the overall goals of the project are to document the current state of flora on Mt. Tam and to establish a benchmark for exploring climate-related shifts in distribution. The Academy is undertaking this project also as a “test case” for the new citizen science program focused on California biodiversity.

We gathered at the Throckmorton Fire Station on Mt. Tam. Alison explained to the group how our teams would work in the field, each led by a professional botanist. In our case it was Ann Howald, a consulting botanist. Our group consisted of five people—Ann led the group; Jennifer, a university student, was our photographer (a GPS-enabled camera was provided by the organizers of the event); Mike, a MMWD volunteer, was our specimen name and details recorder; specimen field presser was Zach, another university student; and I was assigned the task of collecting the specimens themselves.

We were given a map showing our designated target in lat/long, an area called Laurel Dell.

Once we arrived at our site, a 30-foot length of string was stretched out from the lat/long coordinate, marking the perimeter. The length of the string represents the margin of error of the GPS signal. We collected plant samples from within this perimeter, which we marked with blue pin flags.

Ann flagged plant samples with color-coded tags suggesting different tasks: yellow = photograph only; red = photograph and collect. Only plants that are flowering or fruiting are collected, since the reproductive parts are important in identification. All other plants are just photographed. Jennifer took a geo-referenced photograph each specimen and Mike wrote down the scientific name, verified by Ann. If the specimen was a tree, Ann instructed me to clip a small branch. If it was a small plant, I was instructed to try to dig it up with roots as intact as possible.

Ann showed us how to place our sample in our field plant press; a canvas case with stacks of cardboard and newspaper cut into 11 x 16“ tabloid size sheets. If the specimen is too large for the sheet, you can try to bend the stem or root up to fit. If it's really large, you are allowed to cut the specimen in half and spread it over two sheets. For trees there is a separate brown bag for collecting items like acorns and pinecones. For mosses we used a separate white bryophyte packet.

Each specimen is assigned a field collection code, which is the last name of the botanist followed by a number. This is written on the sheet of newspaper that wraps the specimen before pressing between the sheets of cardboard, and is important to link the specimen back to the information on the data sheet

We repeated this process through the day for our area, then headed back to the fire station to transfer our samples to the official specimen press. This consists of similar sheets of cardboard, surrounded by wooden frames, strapped together tightly. The plants are often left out to dry for weeks, but for our specimens, Alison took the plant presses back to the Academy and put them in a temperature-controlled drier, which dries the plants in about five days.

After drying, the identification of the specimens is then verified by a member of the Academy’s Botany department. Then labels are made and a different group of volunteers mount the specimens on the herbarium sheets to be added to our plant collection here at the Academy!

Having the plants in our herbarium collection provides a definitive occurrence record for each species found on the watershed. These records can be compared with our historic collections from Mt. Tam to understand how species distributions may have already changed, and also provides a baseline for future monitoring of change over time. The Academy can also use this information to make recommendations to land managers like the MMWD for conservation outcomes.

For both the collected and the photographed-only plants, the specimen information and geo-located photos are uploaded to Calflora. Calflora stores the data and the photos in one place, and allows for mapping of the plant species locations on the watershed so we can begin to understand distribution of species on Mt. Tam.

I thoroughly enjoyed the opportunity to participate in actual science! And to "get my hands dirty!" I would highly recommend it to others. This survey was the last one of four that took place in 2012, which covered 1/3 of the watershed and documented over 400 species of plants (out of the known 900 or so species on the watershed). The next opportunity will begin in March 2013, Alison says, and the field work will shift to a different area of the watershed. To learn more, visit the Academy’s Citizen Science website.

Jeroen Lapré is the Senior Technical Director of the Visualization Studio at the Academy. He has worked on in-house planetarium productions since the Academy re-opened in 2008—Fragile Planet, LIFE: A Cosmic Story and Earthquake.


  • Volunteer Program

    Jeroen, thank you for explaining the field process so well! We can't wait to do our next series of BioBlitzes in the spring.

  • mmwd volunteer program

    We have honed our process over two year and now use iNaturalist for the data uploads but this is still a great explanation of a BioBlitz field day!

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