**You will need to keep the plants alive throughout the semester so you can describe and document their progress for lab points. Follow directions below carefully.
Plant Terrariums
(this exercise is adapted from Zooinverse / MicroPlants Team: Botanical Collections at the Field Museum https://static.zooniverse.org/microplants.fieldmuseum.org/pdfs/MossLiverwortTerrarium.pdf)
The bryophytes are lycophytes comprise a collection of some of the first plants to diverge from other terrestrial plants.
As we will discuss later in the semester, bryophytes have several traits that confine them to living in moist environments. Additionally, many are well adapted for shady environments. Some club mosses are also adapted for moist, shady environments. Moist, shady environments can be achieved creating terrariums, enclosed clear containers with plants and sometimes other organisms.
We will investigate effects of light levels on the absolute and relative growth rates of a bryophyte, a moss, and a clubmoss. Each of us will create two similar terrariums, one of which will be covered with a screen to reduce light levels. We will compare the growth of the three plants in each environment to see whether each fares better in high or low light and whether the patterns are similar or different between them.
Example of a terrarium in a glass jar. Licensed CC 2.0 by Luis Perez.
4 clear plastic bowls (2 with holes, 2 without holes)
Bag of gravel
Bag of potting soil (with high peat concentration)
3 cups with plants
liverwort
moss
spikemoss (sometimes referred to as clubmoss below)
Ruler, Permanent marker, and stickers (from bag marked 'General')
(adapted from Zooinverse / MicroPlants Team: Botanical Collections at the Field Museum https://static.zooniverse.org/microplants.fieldmuseum.org/pdfs/MossLiverwortTerrarium.pdf)
Image by B. Montgomery. CC BY-NC-SA 2.0
Students place one terrarium in a brighter/ sunnier location & one in a shadier location. They submit initial photos to Padlet,, and they submit follow-up photos intermittently throughout the semester to the same Padlet (I organize the Padlet into columns, and each student gets their own column; it helps for instructor to pre-label columns with student names so they are in same order as gradebook.)
There is no consistent difference between light and shade terrariums across students, probably because of differences in watering and what they consider to be bright or more shaded. However, the replicate terrariums in different locations helps to ensure that one terrarium at least survives the semester.
I buy white pebble/gravel and potting soil from a garden store. I buy plastic disposable bowls from Amazon (not sure this is the same brand, but something like this linked bowl. I drill ~ 8 holes ~ 1/4" diameter in the "lid" bowls using a drill - before I started doing this, there were problems with fungus/mold.