1. What is Soil?
T Webb HHS

2. What is Soil? - humus: biotic community - organic/biological materials
- minerals
- clays and silts
- “dirt”
* contains air and water; is a media for
plant growth and life

3. Criteria for Soil? - naturally occurring - more than 10 cm thick
- supports plant growth
- contains organic materials
- variable composition with depth
* Soil - “Giver of all Life” - many
cultural differences in appreciation

4. Statistics and other stuff… - 10% of Canada’s land is agricultural
- soils vary within small areas
- in a hectare (100 m x 100 m), with a field containing
20 cm depth of soil, the volume will be m3.
- for good farming, typical soil has a density of
1.40 g/cm3 (1400 kg/m3)
- average % of organic material: 2 - 3%
- you need kg of manure to increase organic
materials by 1%; manure is ~ 75% water by volume…
- farmers need to put on 3x the amount of manure to
make up for the water content.

5. How long does it take for soil to form?
- In N.S. the Pleistocene Glacial age resulted in many
depositions of loose till. This occurred ~
years ago.
- Parent material takes on average years for
~ 50 cm of soil to develop. This data is consistent
across Canada.
- The rate of topsoil production can be marginally
increased by adding peat moss and compost.
- soil texture is very important in the classification
process, and for understanding development. The
texture is based on the percent of sand, silt and clay.

6. Characteristics of Soil
pH porosity
humus content temperature
water content particle size(s)
nutrient levels (K, Na, Mg, C, N2, P4, SO42-, etc)
texture compaction
depth of layers density
depth of soil % composition
drainage character
location origin of parent material
biological activities colour