Wednesday, October 27, 2010
Silt Sand and Clay, Horray!
Today's lesson in the garden: what's really beneath our feet? Exploring the garden's soil in three stations was how our plan was set up. At the first station our students collected some soil on the outskirts of the Three Sisters section and with their sight, scent and touch examined this soil. Next they put that soil in group water bottles and observed what happened to their dirt as water from a watering can was added. This brought out oohs and ahhs and these students had never thought about all the different minerals and such that was in the dirt right below their feet. At the second station, their senses were tested again.
Three trays full of sand, clay and silt were passed around and using sight touch and smell our students deduced the differences between the three. Surprisingly these Florida natives had no idea that most of the soil in Florida was made up of these three elements. The third and final station was a grain station! For this experiment we took plastic graduated cylinders covering the top with pantyhose and laying down some silt on one, sand on another and clay on a third. After this preparation water was poured over them and we watched as the water escaped into the graduated cylinder. We were testing the grain size of the different textured sediments. This was by far the favorite of the students in our groups and this lesson was great to teach about what makes up the base of the garden.