St. Croix River Institute Tuesday, June 28: Macroinvertebrates & Forestry Inquiry

CGEE STUDENT VOICE
By Steven Beardsley
Tuesday June 28, 2016 – Day 2

Logos from Yesterday and “Blue River.”

Teachers sharing their logos with each other

David started off the day by having participants go around looking at each other’s logos from the boat trip down the river and the geological inquiry. You can see more of these images on our Facebook album, but we had some pretty creative ones. David also had participants share their logos and go over some feedback on instruction that was provided from yesterday. This feedback led to Ed looking up some maps on google on the topography of Interstate Park where the glacial potholes formed. You can take a look here. We also had more instructors introduce themselves such as Janine Kohn from the Minnesota DNR and Project WET along with Sil talking more about the Jeffers Foundation and the workshops they provide for teachers too.

Logo on the Glacial Potholes 

Logo on the River Exploration

After some logo sharing and going over some reflections, Janine and Karl led participants in the “Blue River” activity. This activity modeled how water travels down multiple rivers. We had three different lines of teachers with a few at the center passing down different colored beads and macaroni pieces to the very end where other teachers counted and recorded what made it down. We could only pass either one tiny piece of macaroni or bead at a time during winter or when it flooded in spring we could pass everything down at once. Another thing that was added was pollution in the form of small fuzzy balls. Overall, it was a fun hands-on activity and one that can be sustainable with the use of recyclable/biodegradable materials.

Janine walks us through other Project WET resources before going into "Blue River."

Passing down water at the confluence during "Blue River"

Directed Inquiry: Macroinvertebrates

Karl demonstrates how to use a net to collect macroinvertebrates

The second part of the day involved groups splitting off again to do either forest inquiry or macroinvertebrates. The only difference was that the first group would do a directed inquiry (question provided by the instructors) while the second group would do a guided inquiry (questions generated by the students). Jenni and I went with the first group for Macroinvertebrates whose question involved seeing if there was a difference in the number of macroinvertebrate species in the man-made lake nearby versus the part of the river by the parking lot. Janine, Karl, and Sil led us in the activity with Karl and Janine demonstrating the use of nets and proper technique in disturbing the water to catch more macroinvertebrates rather than plant debris.


Some teachers also got to try out the large black net that requires two people to hold onto while a second person disturbs the water in front of them.

Using the black net to get a bunch of macroinvertebrates

We did find out that there was a difference in species between the two bodies of water. Actually, one of the teachers, Sam, found a damselfly in addition to a slug and even a snail in the St. Croix River.

Teacher Sam with her damselfly

We also saw some water boatmen, and other teachers got adventurous and looked at some of the murkier water in the little marsh by the water. There was indeed a larger diversity of macroinvertebrates in the river water that indicates healthy water quality while the man-made lake had fewer species.

Open Inquiry: Forestry

This group presenting what they found about the soil in the area

Since we were the first group to do macroinvertebrates we naturally became the second group to do forestry. This time we got to choose our own question based on looking at changes along forest transect lines from the river. Jenni and I had done something similar at Hamline through the Conservation Biology class, but, Terry, the other instructor, suggested that we could look at deer browsing and how it changes from 40 feet from the river but just off the trail to about 90 feet into the forest. We hypothesized that the farther away from the river we would encounter more browsing. What we counted as browsing was any evidence that a deer had nipped at the leaves of a plant.

We actually found that the amount of browsing decreased to zero because we encountered a large clearing in the forest with only large trees that deer couldn’t get to. Other groups did similar studies looking at different species such as buckthorn while others looked at the soil. We began to wonder what caused the large clearing in the forest, and Terry and David both suggested that it could be due to earthworms in that area preventing small plants from growing. To be sure, we could test it by putting a solution of mustard and oil in the earth, which apparently is an irritant to earthworms and causes them to leave the earth.

Concluding Thoughts

Instructor David guides us down the transect line from the river

This was another great day of reflection and inquiry. I also learned a lot when it came to doing forest investigation and thinking about the different plant species and deer browsing. Teachers also got to experience the difference between directed and guided inquiry. Personally, I think guided inquiry also takes the form of research papers and projects, which I think can be a great way for students and individuals to take control of their learning. Tomorrow is, sadly, the last day of the institute, but teachers have a lot to look forward to as we wrap up “Sum of the Parts” and do some Engineering challenges.