Soil 50% pores and 50% solids www.PhysicalGeography.net
Slide 3
Sand A soil solid No electrical charge No electrical charge
Very large pore spaces Very large pore spaces Water drains rapidly
Water drains rapidly
Slide 4
A soil solid Clay A soil solid Retains nutritional elements
(due to negative electrical charge) Retains nutritional elements
(due to negative electrical charge) Very small pore spaces Very
small pore spaces Water drains very slowly Water drains very
slowly
Slide 5
www.spectrumanalytic.com (A cation is an atom with a positive
charge) 20 MILLION hydrogen atoms laid in a line would equal 1
mm
Slide 6
N +/- P + K + S - Ca + Mg + Fe + Mn + Cu + Zn + B + Mo - Al +
Primary nutrients Secondary nutrients Micronutrients {Ni + and Cl -
are sometimes included} http://Plantsinaction. science.uq.edu.au
Most of the nutrients that plants need have a positive electrical
charge. 0.25mm) (i.e. >0.25mm)">
Sandy Loam Good soil for a garden is SANDY LOAM -less silt and
clay and more sand than a true loam -sand should be predominately
coarse and medium sized particles (i.e. >0.25mm) (i.e.
>0.25mm)
Slide 37
Clay soils are usually: Fertile - negative charge so good
nutrient retention (storehouse) Fertile - negative charge so good
nutrient retention (storehouse) Tend to compact and thus limit O 2
availability Tend to compact and thus limit O 2 availability
Inadequate pore space for good air and water movement Inadequate
pore space for good air and water movement As little as 20% clay
particles result in soil behaving like a clayey, sticky soil. As
little as 20% clay particles result in soil behaving like a clayey,
sticky soil. Source: Colorado State Extension Service Source:
Colorado State Extension Service
Slide 38
SoilTextureTriangle
Slide 39
Slide 40
AMENDMENTS IMPROVING SOIL TILTH Water retention --addition of
organic material -addition of vermiculite (not perlite) -addition
of clay to sandy soil -what about underlying clay soil ?(it will
limit drainage) Pore size Nutrient retention
Slide 41
VERMICULITE VERMICULITE Increases moisture holding capacity
holding capacity Increases pore space PERLITE PERLITE Low water
holding capacity Increases pore space AMENDMENTS
Slide 42
Tilth Suitability of a soil to support plant growth (physical
condition of a soil); -moisture retention -drainage-aeration -ease
of seed germination and emergence -ease of root development &
penetration -ease of tillage
Slide 43
AMENDMENTS IMPROVING SOIL TILTH PROVIDING NUTRIENTS Microbial
activity Microbial activity (see SOIL {2}) Correcting deficiencies
Soil test (LSU pH, P, K, Ca, Mg, Na, S, Cu and Zn)
