THE DIRT ON DIRT
|
In This Lesson:
Soils are living: 5 min Percolation & Soil pH: 30 - 60 min Texture test & Soil Types: 25 - 45min Quality Card & Horizons: 20 - 60min Outro: 5 min Total Lesson Time: 85 - 175 min (1 hour, 25 min - 2 hours, 55 min) |
|
|
Dirt is just dirt, right? You’d be surprised! All that ground that you walk on and grow plants in isn’t just dirt, it’s ~Soil~. Remember folks, dirt is what you get on your hands and clothes, soil is made up of elements that have been decomposing for millenia!
|
Okay, so the dirt below me is alive, that’s not scary at all to think about. If it’s alive, I have to ask, do I take care of it like a pet? How do I know if my soil is healthy? Do I have to feed it or water it? Send it Christmas cards?
Not quite, try out these experiments and learn all about what healthy soil looks like, feels like, and does! Soil Percolation What you’ll need:
What you’ll do:
|
|
Why does it matter?
Healthy soil has worms and other invertebrates that make channels throughout to allow water to reach the roots of plants. Compacted areas, like where people walk on or where machines drive on, lose these channels. It can also indicate whether plants need water, like shown in the picture. If water was poured on saturated soil, it might pool or run off, telling you the plant has enough water.
Kitchen pH Experiment
pH tells scientists, cooks, gardeners, and the rest of us whether something is acidic or basic. It’s based on the concentration of hydrogen atoms and some math, but what you need to know is that pH affects nutrient absorption in plants. Take a look at the pH scale we have here, acidic things like lemons, tomatoes, and vinegar all taste sour. Basic things, like tofu and lentils, often have a slippery taste or texture, but tasting things is not a safe way to measure pH. So how can we test the pH of our soil? Check this out:
What you’ll need:
What you’ll do:
Healthy soil has worms and other invertebrates that make channels throughout to allow water to reach the roots of plants. Compacted areas, like where people walk on or where machines drive on, lose these channels. It can also indicate whether plants need water, like shown in the picture. If water was poured on saturated soil, it might pool or run off, telling you the plant has enough water.
Kitchen pH Experiment
pH tells scientists, cooks, gardeners, and the rest of us whether something is acidic or basic. It’s based on the concentration of hydrogen atoms and some math, but what you need to know is that pH affects nutrient absorption in plants. Take a look at the pH scale we have here, acidic things like lemons, tomatoes, and vinegar all taste sour. Basic things, like tofu and lentils, often have a slippery taste or texture, but tasting things is not a safe way to measure pH. So how can we test the pH of our soil? Check this out:
What you’ll need:
- 2 tablespoons vinegar or lemon juice
- 2 tablespoons baking soda
- 2 containers with water, about a half cup of water in each
- A sample of your soil (roughly 4 tablespoons)
- (This experiment might require materials you don’t have access to, luckily it is very basic and doesn’t always give us information we can use. If you don’t have the materials, you can still answer the questions on step 4)
What you’ll do:
- Mix the vinegar or lemon juice into one of the containers of water, mix the baking soda into the other
- Add roughly two tablespoons (or a large spoonful) of soil to each container.
- On your Soil Experiment page in your nature journal, start a new paragraph section and label it : “Kitchen pH Experiment”. Make a note in your nature journal about any observations. If you saw bubbles and a reaction in the vinegar mixture, you have fairly basic soil. If you saw bubbles or other signs of a reaction in the baking soda mixture, you have fairly acidic soil.
- What are some limitations of this experiment? (What can we learn from this test and what can’t it tell you?) Answer in your nature journal
|
Sediment Jars
|
What you’ll need:
What you’ll do: |
|
Home on the Loam Song to the Tune of Home on the Range
Chorus: Home, home on the loam That’s made of sand, silt, and clay where we can’t recall a dry day at all, and the worms rejoice every day. Oh, give me a home on rich, fertile loam, that grows our forests today, Where we can’t recall a dry day at all, and the fungi rejoice ev’ry day. |
Chorus
Oh in my home, with that clay loam That holds the water so well Where it rains a lot, and the kids are all taught To love the puddles and smell Chorus Oh, give me a home with plentiful loam that’s made of sand, silt, and clay. No one can debate that its texture is great, and the forests grow more ev’ry day. Chorus x2 |
|
Now that you’ve learned about three major qualities of soil: Percolation (how fast water moves through it), pH (nutrient quality and acidity), and content of your soil (of sand, silt, and clay), check out the OSU Willamette Valley Soil Quality Card. Pick one quality from the guide and tell us about it here:
|
|
|
|
Soil horizons or soil profiles are a way we can classify and characterize soil as we go deeper and deeper. There are a few distinct layers: Humus (the organic materials like leaves, pine needles, sticks, etc. being decomposed), Topsoil (the nutrient rich layer), Subsoil (usually the deepest water from the surface goes and mineral rich), and bedrock (where the soil horizons stop).
|
Other activities & Resources
|
|
|
|
|
