Soil Sand, Silt, Clay

Soil The outer layer of the earth’s crust, supports

plant growth.

Mineral matter is the non-living substances that make up soil.

It is rock that weathered to make up soil. • SAND, SILT, CLAY

Texture is determined by the percentage of sand, silt and clay present in the soil.

Sand Largest Soil Particle, you

can see each particle

Good aeration and water flow.

Poor WHC and Cation Exchange Capacity=CAN’T HOLD NUTRIENTS

Silt

Mixture of sand and clay

Mid-size particle, holds water and nutrients.

Feels like flour when dry and smooth when wet.

Clay

Smallest Soil Particle, holds water and nutrients.

Poor aeration and water drainage.

Clumps when dry.

Has the most surface area

Loam When there are equal amounts of

sand, silt and clay.

Humus Organic matter that will not break

down any further. Comes from plant leaves, roots,

stems. Soil with lots of OM will be dark in

color. Organic soil is more productive Kind of like a natural compost

material…

Tilth The ease of which soil can be worked. Moles, earthworms, ants help this

process. • Increase Aeration• Increase Nutrient Content• Increase Water Drainage

Soil Texture Chart Find the

percentage of each soil type.

Where they all meet, is the type of soil.

Let’s Practice! Complete the texture chart

worksheet on your own.

What texture do each of the percentages represent?

Soil Drainage Lab In each of your greenhouse groups… Materials:

• Three potting containers• Three plastic cups• Peat moss• Organic Soil• Regular planting soil

Fill each container with equal amounts of soil and add 1 cups of water.

Allow the containers to drain into the plastic cups for 10 minutes.

Finally, Make your own Mix! Which groups is the best at retaining water!?!