• 45% minerals and nutrients*

• 25% air filled pore spaces

• 25% water filled pores spaces

• 5% organic matter

​

Ideal Soil Composition

*Will be the focus of our lab.

​2.0 - 0.05 mm

​​Sand

​

0.05 - 0.002​ mm

Silt

​

Less than 0.002mm

​​Clay

​

​Soil Types

​Soil characteristics are based on particle size.

Particle Size Effects

• Water and nutrient hold capacity: how much water and nutrients (nitrates & phosphates) and the soil can hold onto

  • Increases as particle size decreases

• Workability: the measure of how easily the soil can be used for specific reasons (AKA - How easily it can be plowed / farmed)

  • Increases as particle size increases

• Aeration: the gas exchange rate

  • Increases as particle size increases

Most soil is not

100% Clay, Silt, or Sand.

Most soil is a mixture. In fact,

the best soil for farming is loam,

a mixture of all three.​

​Textural Triangle

​LOAM

40% Sand

40% Silt

20% Clay​