organic matter

Soil is Not Dirt!

I'm taking Soil Science at NYBG this semester - its a fascinating combination of chemistry, biology and physics - and I just want to let you know that soil is not dirt.  It's a complex mixture of minerals, organic matter, air and water with well-defined structure that varies with the exact components.  

Our instructor defined soil as: "the natural loose covering over most of the earth's land surface that serves as the medium for plant growth".  

To support plant growth, soil needs to provide

  • both root penetration and anchorage - it's physical consistency needs to be loose enough for root penetration but solid enough to anchor the plant
  • water
  • air
  • needed and essential nutrients