6.E.2.3 and 6.E.2.4 - Soil Unit

Soil formation begins with the weathering of_______.

• Humas
• Subsoil
• Litter
• Rock

What effect did over plowing and cutting down trees in the Great Plains during the 1930’s?

• It had little effect
• It increased soil fertility
• It was a primary cause of the Dust Bowl
• Farmers had a great harvest

Decayed organic material in soil is called______.

• Litter
• Silt
• Humus
• Clay

The two main factors that determine the rate of weathering are the TYPE of rock and_____.

• Music
• Climate
• Size of rock
• Weight of rock

The movement of rocks and weathered materials is called_________.

• Chemistry
• Physical
• Weathering
• Erosion

Soil conservation includes all of the following EXCEPT_______.

• Desertification
• Contour plowing
• Terracing
• Crop rotation

Which horizon is made up of partially weathered rocks?

• Horizon A
• Horizon B
• Horizon C
• Horizon D or R

In which horizon is most of the HUMUS?

• Horizon A
• Horizon B
• Horizon C
• Horizon D or R

Which horizon contains clay, silt, minerals, and a little humus?

•  Horizon A
• Horizon B
• Horizon C
• Horizon D or R

There is an unlimited supply of fertile soil.

• True
• False