High School science students from the North Haven Community School took a field trip with their teacher, Kristen McGovern, to the Turner Farm last week to collect soil samples. Using a soil sampler, students carefully collected soil from two different locations on farm property, and deposited them into beakers to study in class.
The soil in one beaker was from an area in the farm that had been recently amended with compost, while the other was collected from an area that had been stripped of nutrients and topsoil (a recent building site on the farm). Students were asked to describe the appearance of each site separately with attention to the following questions:
- Is anything growing at the site?
- What color is the soil?
- What is around the area?
- What has happened at or around the site recently (in the last year)?
- Ask farm manager Brenna Chase what typically happens at each site - what each area is used for.
- How easy is it to take a soil sample at each site?
Based on what students observed about each site and what samples looked like, students were asked to surmise which beaker of soil would contain the most microorganisms (microbes) and why. They were also asked to hypothesize which site they believed would host more different types of microbes.
As students explored the farm grounds, they examined the land and made their hypotheses. Following a soil sampling demonstration by Kristen, each student was instructed to take his or her own 3 inch soil sample from each site and deposit in the corresponding beaker. This is called a 'composite' sample from a certain area, and a subsample of all of the soil in each general area.
After returning to school, the students discussed serial dilutions. They examined each beaker of soil collected from the farm, and reported their findings to farm staff the following week.
We hope to host more students at the farm in the coming months to facilitate the hands-on approach to science that their teachers provide!
Thanks to Kristen McGovern for supplying us with information from her lesson plan for this post.
(Words and Image: Amy Peterson)